---
title: "Sitemap — monitoring glossary"
description: "A sitemap is an XML file that lists every URL on a website intended for search engines to index, along with metadata like last modification date and…"
canonical: "https://lemwatch.com/glossary/sitemap"
source: "https://lemwatch.com"
---

# Sitemap

> A sitemap is an XML file that lists every URL on a website intended for search engines to index, along with metadata like last modification date and priority. It is the primary mechanism for telling Google and Bing what to crawl.

## Definition

 Sitemaps follow the sitemaps.org protocol and live at any URL, conventionally /sitemap.xml. Large sites split into a sitemap index pointing to multiple sub-sitemaps (max 50,000 URLs or 50 MB each). Each entry can carry `<lastmod>`, `<changefreq>`, and `<priority>`.

 Sitemap discovery happens via robots.txt (`Sitemap:` directive), Google Search Console submission, Bing Webmaster Tools, and the IndexNow protocol for instant push notifications.

## Why it matters

 Without an accurate sitemap, search engines have to discover URLs by crawling internal links — slower, less reliable, and worse for newly published content. Keeping `<lastmod>` accurate is one of the strongest freshness signals in modern SEO.

 See it in the product: [Sitemap monitoring](https://lemwatch.com/features).


## Related

- [Monitoring glossary](https://lemwatch.com/glossary)
- [SEO](https://lemwatch.com/glossary/seo)
- [robots.txt](https://lemwatch.com/glossary/robots-txt)
- [Indexing](https://lemwatch.com/glossary/indexing)
- [IndexNow](https://lemwatch.com/glossary/indexnow)
- [Canonical Tag](https://lemwatch.com/glossary/canonical)
- [All monitoring checks](https://lemwatch.com/features)
- [SLA (Service Level Agreement)](https://lemwatch.com/glossary/sla)