1.7 XML sitemapsMediumInferred
lastmod missing or always-now
An accurate lastmod helps Google prioritise recrawling changed pages. If it is missing, or set to the current time on every generation, it tells Google nothing useful and can train it to ignore the field.
What it is
No accurate last-modified dates.
Why it matters
Google uses lastmod as a recrawl hint; inaccurate values erode trust in it.
How to fix it
Emit accurate lastmod reflecting real changes.
How to find it on your site
- Inspect the lastmod values across the sitemap.
- Check whether they reflect real content changes or just the build time.
- Set lastmod to the genuine last-modified date of each page.
- Avoid bumping it when nothing meaningful changed.
Cross-reference to ranking and citation factors
A truthful lastmod supports crawl efficiency and freshness. A fake one is discounted and can reduce trust in the signal.
Impact
Low-medium recrawl efficiency. Inferred.
Evidence
Accurate lastmod aids recrawl scheduling. Google Search Central, Build and submit a sitemap