A strong technical foundation is the backbone of any successful SEO strategy. While content quality and backlink authority are critical, the unseen elements of a website—its speed, crawlability, and overall architecture—often determine whether a site can fully realize its potential in search engine rankings. For SEO professionals, web developers, and digital marketers, a technical SEO audit is not just a task—it's a necessity.
A technical SEO audit evaluates how well a website adheres to the best practices that allow search engines like Google to efficiently crawl, index, and rank content. Unlike content or off-page SEO, which focuses on relevance and authority, technical SEO ensures the site works well under the hood so that content can be seen by both users and crawlers.
For those managing websites, the task of conducting a technical SEO audit can be daunting—especially if you're not a developer. That's where a technical SEO checklist comes in. A checklist not only provides structure but also ensures that no critical element is overlooked during the audit process. In 2025, downloadable PDF versions of these checklists have become a staple for professionals and businesses alike. They offer a portable, organized, and easy-to-reference format that can be used across multiple platforms and teams.
This guide explores the concept of technical SEO audit checklists, their importance, and how to effectively use them in your digital strategy. We will delve into the core components of a technical SEO audit, the benefits of using a checklist in PDF format, and how it can streamline your workflow. Whether you are a seasoned SEO specialist or a business owner looking to improve your online presence, this guide will equip you with the knowledge and tools to conduct a comprehensive technical SEO audit.
Understanding the Technical SEO Audit Process
A technical SEO audit is a structured evaluation of a website's technical elements to ensure it meets the standards required for optimal performance in search engines. This audit goes beyond content and backlinks to examine the underlying infrastructure of a site. The process involves identifying and resolving technical issues that may hinder search engines from crawling, indexing, and ranking the site effectively. Key areas of focus include site speed, crawlability, indexing, mobile usability, structured data, and security.
The primary goal of a technical SEO audit is to improve the visibility of a website in search engine results pages (SERPs). Search engines like Google use complex algorithms to assess the quality and relevance of websites, and technical SEO plays a crucial role in this assessment. A site that is technically sound is more likely to be crawled and indexed efficiently, which increases the chances of appearing in relevant search results. Additionally, a well-optimized site provides a better user experience, which is another factor that search engines consider when determining rankings.
One of the most significant benefits of a technical SEO audit is that it helps identify and resolve issues that may not be immediately apparent to the average user. For example, crawl errors can prevent search engines from accessing important pages, while slow loading times can lead to high bounce rates. By addressing these issues, a site can improve its overall performance and user satisfaction. This, in turn, can lead to higher search engine rankings and increased organic traffic.
Key Areas Covered in a Technical SEO Audit
A comprehensive technical SEO audit typically covers several key areas that are essential for the overall health and performance of a website. These areas include:
Crawlability and Indexing: This involves ensuring that search engines can access and understand the content of a website. Crawlability refers to the ability of search engine bots to navigate a site and access its pages, while indexing refers to the process of adding these pages to the search engine's index. Issues such as broken internal links, noindex tags on important pages, and restrictive robots.txt files can hinder this process.
Page Speed and Performance: Page speed is a critical factor in both user experience and search engine rankings. A slow-loading website can lead to high bounce rates and poor user satisfaction. Technical SEO audits evaluate factors such as image optimization, caching, and code efficiency to improve loading times.
Mobile Usability: With the increasing use of mobile devices, it's essential to ensure that a website is optimized for mobile users. This includes checking for responsive design, touch-friendly navigation, and proper font sizes.
Structured Data: Structured data helps search engines understand the content of a website. By implementing schema markup, a site can enhance its visibility in search results with rich snippets, which can increase click-through rates.
Security: A secure website is more likely to be trusted by both users and search engines. Technical SEO audits check for SSL certificates, secure payment gateways, and protection against malware.
Sitemaps and Robots.txt: These files guide search engines through a website. A sitemap provides a list of all the pages on a site, while robots.txt tells search engines which pages to crawl and which to ignore.
Core Web Vitals: Google's Core Web Vitals are a set of performance metrics that measure key aspects of the user experience, such as loading speed, interactivity, and visual stability. These metrics are now a ranking factor, making them an essential part of any technical SEO audit.
By addressing these areas, a technical SEO audit ensures that a website is not only accessible to search engines but also provides an optimal experience for users. This comprehensive approach helps in building a strong technical foundation that supports long-term SEO success.
The Role of a Technical SEO Checklist in PDF Format
A technical SEO checklist in PDF format serves as a practical and structured tool for conducting a comprehensive audit of a website's technical elements. Unlike a simple list of tasks, a checklist provides a clear roadmap that guides users through the audit process, ensuring that no critical element is overlooked. PDF format adds an extra layer of convenience, as it allows for easy downloading, printing, and sharing, making it an accessible resource for both individuals and teams. The portability of a PDF checklist means that it can be used across different platforms and devices, enabling users to refer to it while working on their computers, tablets, or even mobile devices.
One of the primary advantages of using a PDF checklist is its ability to organize audit tasks into logical sections. This structured approach helps users to systematically address each aspect of a website's technical SEO, from crawlability and indexing to page speed and mobile usability. By breaking down the audit into manageable steps, a checklist reduces the complexity of the process and makes it more approachable for those who may not have a technical background. This is particularly beneficial for marketers, bloggers, and small business owners who may not have the expertise to conduct a technical audit from scratch but still need to ensure their site is optimized for search engines.
Moreover, a PDF checklist can be customized to suit the specific needs of a website or a business. Users can add notes, highlight areas of concern, and track the progress of their audit in real-time. This level of customization allows for a more personalized approach to technical SEO, enabling users to focus on the areas that are most relevant to their goals. For example, a small e-commerce store may prioritize improving page speed and mobile usability, while a content-driven blog may focus on crawlability and structured data.
Practical Benefits of a Technical SEO Checklist
The use of a technical SEO checklist in PDF format offers several practical benefits that can significantly enhance the audit process. One of the most notable advantages is the ability to track progress and ensure that all tasks are completed efficiently. A checklist provides a clear record of the audit, making it easier to identify areas that need attention and to monitor the effectiveness of the fixes implemented. This level of organization is particularly useful for large websites with multiple pages and complex structures, where it can be challenging to keep track of all the technical elements.
Another benefit of using a PDF checklist is the ease with which it can be shared and collaborated on. In a team setting, a checklist can serve as a central document that everyone can refer to, ensuring that all members are on the same page and working towards the same goals. This collaborative approach can streamline the audit process and improve the overall efficiency of the team. Additionally, the ability to print the checklist allows for a more hands-on approach, as users can physically mark off completed tasks and note areas that require further attention.
A technical SEO checklist also serves as a valuable reference tool for future audits. Once a website has been optimized based on the checklist, it can be used as a benchmark for future evaluations, helping to identify any new issues that may arise. This ongoing use of the checklist ensures that a website remains technically sound and continues to meet the evolving standards of search engines.
In summary, a technical SEO checklist in PDF format is a powerful tool that simplifies the audit process, enhances collaboration, and ensures that all critical elements of a website are addressed. Its structured approach, portability, and customizability make it an indispensable resource for anyone looking to improve their website's technical SEO and overall performance in search engine rankings.
Key Components of a Technical SEO Audit Checklist
A technical SEO audit checklist is a structured document that outlines the essential steps and tasks required to evaluate a website's technical performance. These checklists are typically divided into several key sections, each focusing on a specific aspect of technical SEO. The following table provides an overview of the most common components found in a technical SEO audit checklist, along with a brief description of each section.
| Section | Description |
|---|---|
| Crawlability & Indexing | Ensures that search engines can access and understand the website's content. This includes checking for crawl errors, noindex tags, and robots.txt settings. |
| Page Speed Optimization | Focuses on improving the website's loading speed through techniques such as image optimization, caching, and code efficiency. |
| Mobile Usability | Evaluates the website's performance on mobile devices, including responsive design, touch-friendly navigation, and proper font sizes. |
| Structured Data | Involves implementing schema markup to help search engines understand the content of the website and display rich snippets in search results. |
| Security | Checks for SSL certificates, secure payment gateways, and protection against malware to ensure the website is secure and trustworthy. |
| Sitemaps and Robots.txt | Reviews the sitemap and robots.txt files to guide search engines through the website and specify which pages should be crawled. |
| Core Web Vitals | Assesses the website's performance based on Google's Core Web Vitals, which include metrics such as loading speed, interactivity, and visual stability. |
Each of these sections plays a crucial role in the overall health and performance of a website. By systematically addressing each component, a technical SEO audit ensures that the website is optimized for both search engines and users. The checklist serves as a roadmap that guides users through the audit process, helping to identify and resolve issues that may be hindering the website's visibility and performance in search results.
Detailed Breakdown of Key Sections
Crawlability & Indexing: This section is essential for ensuring that search engines can access and understand the website's content. Crawlability refers to the ability of search engine bots to navigate the site and access its pages, while indexing refers to the process of adding these pages to the search engine's index. Issues such as broken internal links, noindex tags on important pages, and restrictive robots.txt files can hinder this process. By addressing these issues, the website can improve its visibility in search results.
Page Speed Optimization: Page speed is a critical factor in both user experience and search engine rankings. A slow-loading website can lead to high bounce rates and poor user satisfaction. This section focuses on optimizing the website's loading speed through techniques such as image optimization, caching, and code efficiency. By improving page speed, the website can enhance its performance and user satisfaction.
Mobile Usability: With the increasing use of mobile devices, it's essential to ensure that the website is optimized for mobile users. This section evaluates the website's performance on mobile devices, including responsive design, touch-friendly navigation, and proper font sizes. By addressing these issues, the website can provide a better user experience for mobile users, which can lead to higher search engine rankings.
Structured Data: Structured data helps search engines understand the content of the website. By implementing schema markup, the website can enhance its visibility in search results with rich snippets, which can increase click-through rates. This section ensures that the website's content is properly structured and optimized for search engines.
Security: A secure website is more likely to be trusted by both users and search engines. This section checks for SSL certificates, secure payment gateways, and protection against malware to ensure the website is secure and trustworthy. By addressing these issues, the website can improve its credibility and user trust.
Sitemaps and Robots.txt: These files guide search engines through the website. A sitemap provides a list of all the pages on the site, while robots.txt tells search engines which pages to crawl and which to ignore. By reviewing these files, the website can ensure that search engines are able to navigate and index its content effectively.
Core Web Vitals: Google's Core Web Vitals are a set of performance metrics that measure key aspects of the user experience, such as loading speed, interactivity, and visual stability. These metrics are now a ranking factor, making them an essential part of any technical SEO audit. By optimizing for Core Web Vitals, the website can improve its performance and user satisfaction.
By addressing each of these sections, a technical SEO audit ensures that the website is not only accessible to search engines but also provides an optimal experience for users. This comprehensive approach helps in building a strong technical foundation that supports long-term SEO success.
Best Practices for Using a Technical SEO Checklist PDF
To maximize the effectiveness of a technical SEO checklist in PDF format, it's essential to follow best practices that ensure a thorough and efficient audit. The first step is to familiarize yourself with the structure of the checklist and understand the purpose of each section. This will help you approach the audit with a clear plan and avoid overlooking any critical elements. Start by downloading the checklist and printing it out or keeping it open on your computer for easy reference. If you're working in a team, make sure everyone has a copy of the checklist and is aware of their responsibilities.
Once you have the checklist ready, the next step is to conduct a preliminary review of your website to identify any obvious issues. This can include checking for broken links, ensuring that all pages are accessible, and verifying that the site loads quickly. This initial assessment can help you prioritize the most urgent tasks and focus on areas that are likely to have the greatest impact on your website's performance. As you go through the checklist, mark off completed tasks and note any issues that need further attention. This will help you track your progress and ensure that no task is left unaddressed.
One of the best practices for using a technical SEO checklist is to break down the audit into manageable sections and tackle them one at a time. This approach allows you to focus on each area without feeling overwhelmed by the sheer volume of tasks. For example, you can start with the crawlability and indexing section, followed by page speed optimization, and then move on to mobile usability. By following this structured approach, you can ensure that each section is thoroughly addressed before moving on to the next.
Another important best practice is to use the checklist as a reference throughout the audit process. As you work through each task, refer back to the checklist to ensure that you are following the correct procedures and not missing any key steps. If you encounter any questions or uncertainties, use the checklist as a guide to help you determine the appropriate course of action. Additionally, make sure to document any findings or issues that you encounter, as this information can be valuable for future audits and for tracking the progress of your website's technical SEO.
Collaboration is also a key best practice when using a technical SEO checklist. If you're working with a team, assign specific tasks to each member and use the checklist to coordinate your efforts. This will help ensure that everyone is on the same page and that the audit is completed efficiently. Regular check-ins and progress updates can help identify any challenges or roadblocks early on, allowing you to address them before they become major issues.
Finally, it's important to treat the technical SEO checklist as a living document that can be updated and refined over time. As you conduct the audit and implement changes, use the checklist to track the effectiveness of your efforts and make adjustments as needed. This ongoing use of the checklist ensures that your website remains technically sound and continues to meet the evolving standards of search engines. By following these best practices, you can make the most of your technical SEO checklist and achieve optimal results for your website.
Comparing Technical SEO Audit Checklist PDFs from Different Providers
Different providers offer a variety of technical SEO audit checklists in PDF format, each with its own unique features and benefits. These checklists are designed to help users conduct a comprehensive audit of their websites, but they can vary in terms of structure, depth of content, and ease of use. The following table compares three popular technical SEO audit checklists from different providers, highlighting their key features and strengths.
| Provider | Features | Depth of Content | Ease of Use | Customization |
|---|---|---|---|---|
| TECHenya Solutions | Comprehensive sections on crawlability, indexing, page speed, and security. Includes actionable steps and downloadable templates. | High | Medium | High |
| Rankyak | Focuses on actionable tasks and includes a printable reference guide. Organizes tasks by priority level. | Medium | High | Medium |
| Reliablesoft | Covers SEO basics, technical SEO, on-page SEO, and mobile SEO. Includes a detailed breakdown of tasks and sections. | High | Medium | High |
TECHenya Solutions offers a detailed and well-structured technical SEO audit checklist that covers all the essential areas of technical SEO. The checklist is divided into comprehensive sections that include crawlability, indexing, page speed, and security. Each section provides actionable steps and downloadable templates that users can use to implement changes. The depth of content is high, making it suitable for both beginners and advanced users. While the checklist is thorough, it may be slightly more complex for those who are new to technical SEO.
Rankyak's technical SEO audit checklist is designed to be user-friendly and easy to follow. It focuses on actionable tasks and includes a printable reference guide that users can use to track their progress. The checklist organizes tasks by priority level, allowing users to tackle the most impactful issues first. The depth of content is medium, but the ease of use is high, making it ideal for those who need a straightforward and efficient audit process.
Reliablesoft's technical SEO audit checklist is a comprehensive resource that covers a wide range of topics, including SEO basics, technical SEO, on-page SEO, and mobile SEO. The checklist provides a detailed breakdown of tasks and sections, making it suitable for users who want to take a holistic approach to their audit. The depth of content is high, but the ease of use is medium, as users may need to navigate through multiple sections to find the information they need.
Each of these checklists has its own strengths and is suitable for different users based on their needs and level of expertise. By comparing these checklists, users can choose the one that best aligns with their goals and requirements.
Implementing Technical SEO Checklist PDFs in Your Workflow
Integrating a technical SEO audit checklist into your workflow can significantly streamline the audit process and ensure that all critical elements are addressed. The first step is to download the checklist and make it a part of your regular SEO maintenance routine. Whether you're working on a single website or managing multiple sites, having a checklist in PDF format allows you to keep track of your progress and ensure that no task is overlooked.
One effective way to implement the checklist is to schedule regular audits at set intervals, such as monthly or quarterly. This approach helps you stay on top of any new issues that may arise and ensures that your website remains technically sound. By using the checklist as a reference, you can quickly identify areas that need attention and take corrective action before they impact your search engine rankings. Additionally, the checklist can serve as a training tool for new team members, helping them understand the key elements of technical SEO and how to conduct an audit.
Another important aspect of implementing a technical SEO checklist is to use it as a collaborative tool. If you're working with a team, assign specific tasks to each member and use the checklist to coordinate your efforts. This will help ensure that everyone is on the same page and that the audit is completed efficiently. Regular check-ins and progress updates can help identify any challenges or roadblocks early on, allowing you to address them before they become major issues.
To further enhance the effectiveness of the checklist, consider using it in conjunction with other SEO tools and resources. For example, you can use tools like Google Search Console and Screaming Frog to identify technical issues and track your progress. By integrating these tools with the checklist, you can gain a more comprehensive understanding of your website's performance and make data-driven decisions to improve its technical SEO.
Finally, it's important to treat the technical SEO checklist as a living document that can be updated and refined over time. As you conduct the audit and implement changes, use the checklist to track the effectiveness of your efforts and make adjustments as needed. This ongoing use of the checklist ensures that your website remains technically sound and continues to meet the evolving standards of search engines. By following these steps, you can effectively implement a technical SEO checklist in your workflow and achieve optimal results for your website.
Common Challenges in Technical SEO Audits
Despite the structured approach provided by technical SEO checklists, professionals and businesses often encounter challenges during the audit process. One common challenge is the complexity of technical SEO itself. Many of the tasks involved, such as analyzing crawlability, optimizing page speed, and implementing structured data, require a certain level of technical expertise. For those without a background in web development or SEO, these tasks can be daunting and may require additional training or the assistance of an expert.
Another challenge is the time required to conduct a thorough technical SEO audit. While a checklist can help streamline the process, it still requires a significant investment of time and effort. This is particularly true for large websites with multiple pages and complex structures, where it can be challenging to identify and address all technical issues. Additionally, the need to prioritize tasks based on their impact on search engine rankings can make it difficult to determine which issues should be addressed first.
Resource constraints also pose a challenge for many businesses. Conducting a technical SEO audit often requires the use of specialized tools and software, such as Google Search Console, Screaming Frog, and Ahrefs. While some of these tools are free, others can be expensive, making them inaccessible to small businesses or those with limited budgets. Additionally, the need to hire or train staff to conduct the audit can add to the overall cost and complexity of the process.
Technical SEO audits can also be affected by the changing landscape of search engine algorithms. Search engines like Google regularly update their algorithms to improve the quality of search results, which can render some technical SEO strategies obsolete. This means that even if a website is optimized based on the latest best practices, it may still be affected by algorithm updates that introduce new requirements or penalties for certain technical issues.
Finally, the challenge of maintaining a technically sound website over time is significant. Once a website has been optimized based on a technical SEO audit, it is essential to continue monitoring its performance and making adjustments as needed. This ongoing process requires a commitment to regular maintenance and updates, which can be time-consuming and resource-intensive. Additionally, the introduction of new technologies and features, such as mobile-first indexing and Core Web Vitals, can require additional efforts to ensure that the website remains compliant with the latest standards.
Despite these challenges, the use of a technical SEO checklist can help mitigate many of these issues by providing a structured and organized approach to the audit process. By following the checklist and addressing each task systematically, users can ensure that their website remains technically sound and continues to perform well in search engine rankings.
Frequently Asked Questions About Technical SEO Audit Checklists
Despite the widespread use of technical SEO audit checklists, many professionals and businesses still have questions about their implementation and effectiveness. The following FAQ section addresses some of the most common questions to provide a better understanding of how these checklists can be used to improve a website's technical SEO.
1. How often should I perform a technical SEO audit?
It is generally recommended to perform a technical SEO audit at least once every 3 to 6 months. However, the frequency may vary depending on the size and complexity of the website. For example, large websites with frequent content updates or e-commerce sites with seasonal changes may require more frequent audits. Additionally, it's a good idea to conduct an audit after making significant changes to the website, such as redesigning the site or implementing new features.
2. Do I need technical expertise to use a technical SEO audit checklist?
While some technical knowledge can be helpful, a technical SEO audit checklist is designed to be accessible to users with varying levels of expertise. The checklist provides clear instructions and actionable steps that can be followed even by those who are not technical experts. However, for more complex tasks, such as implementing structured data or optimizing page speed, it may be necessary to seek the assistance of a technical SEO specialist or web developer.
3. Can I use a technical SEO audit checklist for multiple websites?
Yes, a technical SEO audit checklist can be used for multiple websites. In fact, many businesses that manage multiple sites find it beneficial to use a standardized checklist to ensure consistency in their SEO efforts. By using the same checklist for all websites, businesses can easily compare the performance of different sites and identify common issues that may need to be addressed across the board.
4. Are there any tools that can help me with the technical SEO audit process?
Yes, there are several tools that can assist with the technical SEO audit process. Some of the most popular tools include Google Search Console, Screaming Frog, Ahrefs, and SEMrush. These tools can help identify technical issues, such as crawl errors, broken links, and page speed problems, and provide insights into how to resolve them. Additionally, many of these tools offer features that can be integrated with a technical SEO audit checklist to streamline the process.
5. How do I prioritize the tasks in a technical SEO audit checklist?
Prioritizing tasks in a technical SEO audit checklist can be done based on their impact on search engine rankings and user experience. Tasks that have a high impact, such as fixing crawl errors or improving page speed, should be addressed first, as they can have an immediate effect on the website's performance. Tasks with a lower impact, such as optimizing meta tags or improving structured data, can be addressed later. Additionally, it's a good idea to focus on tasks that are easier to implement first, as this can help build momentum and confidence in the audit process.
6. Can a technical SEO audit checklist help improve my website's rankings?
Yes, a technical SEO audit checklist can help improve a website's rankings by identifying and resolving technical issues that may be hindering its performance. By addressing issues such as crawlability, indexing, and page speed, a website can become more accessible to search engines and provide a better user experience. This can lead to higher search engine rankings and increased organic traffic. However, it's important to note that technical SEO is just one aspect of an overall SEO strategy, and it should be combined with other elements such as content optimization and backlink building for the best results.
7. Is it necessary to hire an expert for a technical SEO audit?
While it is not necessary to hire an expert for a technical SEO audit, it can be beneficial in certain situations. For example, if you're dealing with complex technical issues that require specialized knowledge, such as implementing structured data or optimizing Core Web Vitals, it may be necessary to seek the assistance of a technical SEO expert. Additionally, hiring an expert can help ensure that the audit is conducted thoroughly and efficiently, especially for large or complex websites.
8. How can I track the progress of my technical SEO audit?
Tracking the progress of a technical SEO audit can be done using the checklist itself. By marking off completed tasks and noting any issues that need to be addressed, you can keep track of your progress and ensure that no task is left uncompleted. Additionally, using tools like Google Search Console and Screaming Frog can help you monitor the impact of your changes and track improvements in your website's technical SEO over time.
9. Can I customize a technical SEO audit checklist for my specific needs?
Yes, a technical SEO audit checklist can be customized to suit your specific needs. Many checklists are designed to be flexible and can be modified to include additional tasks or exclude those that are not relevant to your website. For example, if your website is an e-commerce site, you may want to add tasks related to product page optimization and shopping cart functionality. By customizing the checklist, you can ensure that it aligns with your goals and addresses the unique needs of your website.
10. What should I do if I encounter technical issues that I can't resolve?
If you encounter technical issues that you can't resolve, it's a good idea to seek the assistance of a technical SEO expert or web developer. These professionals have the knowledge and experience to address complex technical issues and can help you implement the necessary fixes. Additionally, you can refer to online resources and forums to find solutions to common technical SEO issues. Many of these resources provide step-by-step guides and troubleshooting tips that can help you resolve technical issues on your own.
By addressing these common questions, users can gain a better understanding of how to effectively use a technical SEO audit checklist and overcome any challenges they may encounter during the audit process. With the right approach and resources, a technical SEO audit can be a valuable tool for improving a website's performance and achieving long-term SEO success.
Final Thoughts
In the ever-evolving landscape of digital marketing, the importance of a technical SEO audit cannot be overstated. A well-structured technical SEO audit checklist in PDF format provides a clear and organized approach to identifying and resolving technical issues that can hinder a website's performance. By systematically addressing key areas such as crawlability, indexing, page speed, and mobile usability, a checklist ensures that a website is optimized for both search engines and users. This not only improves search engine rankings but also enhances the overall user experience, leading to increased organic traffic and higher conversion rates.
The benefits of using a technical SEO audit checklist extend beyond the initial audit. It serves as a valuable reference tool that can be used for ongoing maintenance and future audits. By regularly reviewing and updating the checklist, businesses can stay ahead of emerging trends and algorithm updates, ensuring that their websites remain technically sound and competitive. Additionally, the checklist can be customized to suit the unique needs of a website, making it a flexible and adaptable resource for both small businesses and large enterprises.
For professionals and businesses looking to improve their technical SEO, the use of a checklist is an essential practice. It not only simplifies the audit process but also ensures that no critical element is overlooked. By following the structured approach provided by a technical SEO audit checklist, users can confidently address technical issues and optimize their websites for long-term success. As the digital landscape continues to evolve, the role of technical SEO will only become more critical, making it imperative for businesses to adopt best practices and leverage the power of a technical SEO audit checklist.