# Sitemap

> How to fix your sitemap: missing sitemap.xml, invalid XML, empty urlset, missing lastmod, stale entries, sitemap-index handling, content type, and the 50k URL limit.

This check carries 2% of the score.

*These remediation guides are written in English.*

<a id="not-found"></a>

## No sitemap found

ax-audit looked for a sitemap in two places and didn't find one:

- The `Sitemap:` directive in `/robots.txt`
- The default fallback path `/sitemap.xml`

Publish a minimal sitemap and reference it from robots.txt:

```
<?xml version="1.0" encoding="UTF-8"?>
<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>https://your-site.com/</loc>
    <lastmod>2026-04-30</lastmod>
  </url>
  <url>
    <loc>https://your-site.com/about</loc>
    <lastmod>2026-04-15</lastmod>
  </url>
</urlset>
```

```
# robots.txt
User-agent: *
Allow: /

Sitemap: https://your-site.com/sitemap.xml
```

> **Framework helpers**
>
> Next.js: use
>
> next-sitemap
>
>  or App Router
>
> sitemap.ts
>
> . Astro:
>
> @astrojs/sitemap
>
> . Hugo, Jekyll, and most static generators ship sitemaps out of the box.

---

<a id="not-xml"></a>

## Sitemap is not valid XML

The response at the sitemap URL doesn't start with `<?xml`, `<urlset>`, or `<sitemapindex>`. Most often this means a 200 HTML error page is being served instead of the sitemap.

- Test directly: `curl -i https://your-site.com/sitemap.xml`
- Make sure the route doesn't fall through to your SPA index.html.
- Validate the output at [xml-sitemaps.com/validate](https://www.xml-sitemaps.com/validate-xml-sitemap.html).

---

<a id="wrong-content-type"></a>

## Unexpected Content-Type

Serve sitemaps with `Content-Type: application/xml` (or `text/xml`). A wrong content type (like `text/html`) causes some crawlers to discard the file before parsing.

```
# Nginx
location = /sitemap.xml {
  default_type application/xml;
}

# Express / Next.js custom server
res.setHeader('Content-Type', 'application/xml; charset=utf-8');
```

---

<a id="empty-urlset"></a>

## Empty <urlset>

Your sitemap is well-formed XML but contains no `<url>` entries. Add at least one URL per page you want crawlers to discover, at minimum the homepage.

---

<a id="empty-index"></a>

## Empty <sitemapindex>

A sitemap-index file must reference at least one child sitemap:

```
<?xml version="1.0" encoding="UTF-8"?>
<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <sitemap>
    <loc>https://your-site.com/sitemap-pages.xml</loc>
    <lastmod>2026-04-30</lastmod>
  </sitemap>
  <sitemap>
    <loc>https://your-site.com/sitemap-blog.xml</loc>
    <lastmod>2026-04-29</lastmod>
  </sitemap>
</sitemapindex>
```

---

<a id="unreachable-children"></a>

## Child sitemaps unreachable

Your sitemap-index references child sitemaps that returned non-2xx responses. Crawlers may give up after the first failure and never reach the rest of your URLs.

- Verify each `<loc>` URL inside the index returns `200 OK`.
- Use absolute URLs only; relative `<loc>` values are invalid per the sitemap spec.
- If a child sitemap is gated by auth or geo-blocked, move it outside the public sitemap.

---

<a id="low-lastmod"></a>

## Low <lastmod> coverage

Less than half of your `<url>` entries declare a `<lastmod>`. AI agents and search crawlers use lastmod to decide what to re-fetch; without it, every URL looks equally fresh (or equally stale).

```
<url>
  <loc>https://your-site.com/blog/post-1</loc>
  <lastmod>2026-04-30</lastmod>
</url>
```

Use ISO 8601 dates (`YYYY-MM-DD` or full timestamps). Most sitemap generators auto-populate this from the page's git history or filesystem mtime.

---

<a id="stale"></a>

## Stale <lastmod>

The newest `<lastmod>` in your sitemap is more than a year old. Crawlers interpret this as "nothing has changed on the site," which slows or stops re-indexing.

- Regenerate the sitemap on every deploy.
- Touch the lastmod when content actually changes; don't blanket-update every URL on every build (crawlers learn to ignore that).

---

<a id="too-many-urls"></a>

## Above the 50,000 URL limit

The [sitemaps.org spec](https://www.sitemaps.org/protocol.html) caps a single sitemap at 50,000 URLs. Split into a sitemap-index pointing to multiple smaller sitemaps:

```
/sitemap.xml              -- index
/sitemap-pages.xml        -- 1 to 5,000 marketing pages
/sitemap-blog-2025.xml    -- 1 to 30,000 blog posts from 2025
/sitemap-blog-2026.xml    -- ongoing blog posts
```

---

<a id="too-large"></a>

## Above the 50 MB size limit

Same fix as above: split the sitemap. The 50 MB limit applies to the *uncompressed* file size. You can also serve sitemaps gzipped (`sitemap.xml.gz`) to reduce transfer size, but the uncompressed limit still applies.

---

Markdown representation of https://axrush.com/guides/sitemap