Introduction: What is a Sitemap?
A sitemap is a file that provides search engines with information about website pages, helping search engines discover and crawl website pages more efficiently. Sitemaps not only tell search engines which pages are important but also provide valuable information such as last modified time, update frequency, multilingual versions, etc.
Although sitemaps are not required, for large websites, new websites, or websites containing a lot of rich media content, sitemaps are important tools for improving search engine indexing efficiency. By properly creating and submitting sitemaps, you can ensure search engines discover and index important pages in a timely manner.
What is a Sitemap?
A sitemap is a file used to provide search engines with information about website pages, videos, and other files, as well as their relationships. Search engines (like Google) read this file to crawl websites more efficiently.
Sitemaps can tell search engines:
- Which pages and files are important
- Last modified time of pages
- Update frequency of pages
- Multilingual versions of pages
- Specific content type information (such as videos, images, news, etc.)
Note that sitemaps help search engines discover URLs but don't guarantee that all items in the sitemap will be crawled and indexed. Search engines decide whether to index pages based on page quality, relevance, and other factors.
Do I Need a Sitemap?
Situations Where Sitemaps Are Needed
- Large Websites: Usually refers to websites with over 500 pages. In large websites, ensuring every page is linked by at least one other page is difficult, and sitemaps can help search engines discover all pages.
- New Websites with Few External Links: Search engine crawlers crawl websites by accessing URLs in previously crawled pages. If other websites don't link to your website, search engines may not be able to discover your pages.
- Websites Containing a Lot of Rich Media Content: If websites contain a lot of videos, images, or news content, sitemaps can help search engines better understand and index this content.
- Websites with Incomplete Internal Linking: If important pages on the website are not linked by other pages, sitemaps can help search engines discover these pages.
Situations Where Sitemaps May Not Be Needed
- Small Websites: Websites with about 500 pages or less. If the website has few pages and all important pages can be accessed through internal links, sitemaps may not be needed.
- Websites with Complete Internal Linking: If search engine crawlers can find all important pages from the homepage through links, sitemaps are less important.
- No Large Amount of Media Files or News Pages: If the website is mainly text content and doesn't need to display videos, images, or news in search results, sitemaps may not be required.
Types of Sitemaps
1. XML Sitemap
XML sitemaps are the most commonly used format, specifically designed for search engines. XML sitemaps use standardized XML format, containing page URLs, last modified time, update frequency, priority, and other information.
XML sitemaps support extensions and can include specific content type information, such as image sitemaps, video sitemaps, news sitemaps, etc. XML sitemap files are usually named sitemap.xml and placed in the website root directory.
2. HTML Sitemap
HTML sitemaps are user-facing navigation pages that display all main page links of the website in webpage format. HTML sitemaps not only help users quickly find content but also assist search engines in discovering pages.
HTML sitemaps are usually organized by category, using clear hierarchy for easy user browsing. Although HTML sitemaps help SEO, their main value lies in improving user experience.
How to Create and Submit a Sitemap
Creating Sitemaps
1. Use CMS Auto-Generation
Most content management systems (CMS) automatically generate sitemaps. If you use platforms like WordPress, Wix, Blogger, etc., sitemaps may already be automatically created and accessible to search engines.
2. Use Online Tools
You can use online tools (such as XML-Sitemaps.com) to generate sitemaps. These tools usually require entering the website URL, then automatically crawl the website and generate sitemap files.
3. Use Next.js to Auto-Generate (Recommended)
If you build your website using the Next.js framework, Next.js provides built-in sitemap generation functionality. By creating an app/sitemap.ts file, Next.js automatically generates a standards-compliant XML sitemap and provides access at the /sitemap.xml path.
Advantages: Automatic generation, no manual maintenance needed, automatically updates when pages are added or modified, supports multiple languages and locales.
Submitting Sitemaps
1. Submit via Google Search Console
The most recommended way is to submit sitemaps through Google Search Console. Log in to Google Search Console, select your website, then go to the \"Sitemaps\" section, enter the sitemap URL and submit. Google will regularly crawl sitemaps and update indexing when new pages are discovered.
2. Declare in robots.txt
You can add the sitemap location in the robots.txt file. Add a line at the end of the robots.txt file: Sitemap: https://example.com/sitemap.xml
Sitemap Best Practices
- Only Include Pages That Need Indexing: Sitemaps should only include pages that need to be indexed by search engines. Exclude noindex pages, duplicate content pages, login pages, 404 pages, pages blocked by robots.txt.
- Keep Sitemaps Updated: When adding new pages or updating existing pages, update the sitemap's lastmod date in a timely manner. If using a CMS or SEO plugin, this is usually automatic.
- Comply with Size Limits: A single sitemap file is limited to 50,000 URLs or 50MB (uncompressed). If exceeding the limit, use a Sitemap Index file to organize multiple sitemap files together.
- Use Correct URL Format: Ensure URLs in sitemaps use absolute paths (including protocol and domain) and match actual website URLs. If the website uses HTTPS, URLs in sitemaps should also use HTTPS.
- Set Reasonable Priority and Update Frequency: Although priority and changefreq are not ranking factors, they can help search engines understand page importance. Homepage is usually set to highest priority, blog posts can be set to daily or weekly.
- Verify Sitemaps: After submitting sitemaps, use Google Search Console to check sitemap status and ensure there are no errors. Common errors include 404 errors, format errors, URLs blocked by robots.txt, etc.