H1 missing or duplicated
57.6%
of the 3,044 free scans considered in the last 30 days raised this finding. That is 1,754 scans across 1,748 distinct sites. 95% interval 55.3% to 59.9%.
What it means
The H1 tells both people and machines what a page is about. None leaves the subject ambiguous; several compete with each other and none wins.
How to fix it
Give each page exactly one <h1> that names its subject, and demote the others to <h2>. If a template puts a logo or a slogan in an H1, move it to a plain element.
How to check it yourself
View source and search for h1. Count how many appear: zero or more than one both mean the H1 is missing or duplicated.
What fixed looks like
View source shows exactly one h1 naming the page's subject, with any others demoted to h2.
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.