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You can provide multiple Sitemap files, but each Sitemap file that you provide must have no more than 50,000 URLs and must be no larger than 10MB (10,485,760) when uncompressed. These limits help to ensure that your web server does not get bogged down serving very large files.

If you want to list more than 50,000 URLs, you must create multiple Sitemap files. If you anticipate your Sitemap growing beyond 50,000 URLs or 10MB, you should consider creating multiple Sitemap files. If you do provide multiple Sitemaps, you can list them in a Sitemap index file. Sitemap index files may not list more than 1,000 Sitemaps.