No robots.txt
5.8%
of the 3,044 free scans considered in the last 30 days raised this finding. That is 178 scans across 170 distinct sites. 95% interval 3.2% to 10.3%.
What it means
robots.txt is where a site states which paths are open to crawlers and where its sitemap lives: its absence leaves both unstated.
How to fix it
Publish a robots.txt at the site root. An empty one that allows everything is fine; a missing one leaves every crawler guessing.
How to check it yourself
Open example.com/robots.txt directly in the browser. If it fails to load or shows an error page instead of plain text, no robots.txt exists.
What fixed looks like
Opening example.com/robots.txt returns a file, even an empty one that allows everything.
How we measured this
Go Voltic scans a site and records which findings it raises. The share above is over every free four-page scan in the last 30 days that loaded at least one page, which is 3,044 scans. Deep scans of paid reports and of the research sweep read a site at a different depth and are a separate population, never in this denominator. It is not a survey and it is not an estimate: it is a count of what our own scanner found. Sites are counted once each in the distinct-sites figure, so a site scanned twice does not weigh double there.
The interval is a 95% Wilson interval. A share printed without its sample size reads as certainty and is indistinguishable from a guess, so both are always shown. Figures on this page were computed on 2026-09-08.
The same share sits beside every other finding on the benchmarks page, which also carries the whole table as CSV and JSON and says how to cite it.
Check your own site
The free scan reads four pages and reports every finding it raises, including this one. It takes about ten seconds and asks for nothing but the address.