Does A11Y_TABLE_HEADERS affect my score?

Yes. It is an importance 5 rule at SPECIFICATION confidence, so a failure costs 5 × 1 points of impact in the Accessibility category before that category is normalised to 100.

What does SPECIFICATION confidence mean?

A standard says so: HTML, WCAG, an RFC or Google's own documentation. Confidence is a declared tier rather than a per-rule number, so every rule backed by the same class of evidence carries the same weight - which is what makes the score reproducible instead of hand-tuned.

How do I check A11Y_TABLE_HEADERS on my own site?

Paste your URL into the box above and it runs only this rule, usually in a couple of seconds. It is also included in the Accessibility checker and in a full scan.

AccessibilityMedium Affects your score

Data tables declare header cells

A11Y_TABLE_HEADERS

Without <th>, a screen reader cannot associate a cell with its column, so the table is read as a meaningless sequence of values.

Free, no signupNo account, no card
No AI in the score986 deterministic rules
Nothing publishedYour scans stay yours
Answers in secondsQuick scan, no browser

How this rule is weighted

Importance: 5 / 10; How much this matters relative to other rules.
Confidence: SPECIFICATION; A standard says so: HTML, WCAG, an RFC or Google's own documentation.
Severity: warning; How the finding is presented when it fails.
Scoring: Counts; A failure costs points in its category.

Impact is importance multiplied by the confidence tier’s weight — SPECIFICATION 1.0, RESEARCH 0.7, EMERGING 0.3, EXPERIMENTAL 0.1. Two rules backed by the same class of evidence therefore always carry the same weight, which is what makes the score reproducible rather than hand-tuned.

Questions about this rule

Does A11Y_TABLE_HEADERS affect my score?: Yes. It is an importance 5 rule at SPECIFICATION confidence, so a failure costs 5 × 1 points of impact in the Accessibility category before that category is normalised to 100.
What does SPECIFICATION confidence mean?: A standard says so: HTML, WCAG, an RFC or Google's own documentation. Confidence is a declared tier rather than a per-rule number, so every rule backed by the same class of evidence carries the same weight - which is what makes the score reproducible instead of hand-tuned.
How do I check A11Y_TABLE_HEADERS on my own site?: Paste your URL into the box above and it runs only this rule, usually in a couple of seconds. It is also included in the Accessibility checker and in a full scan.

Related Accessibility rules

Run the Accessibility checker All 986 rules

Data tables declare header cells

How this rule is weighted

Questions about this rule

Tags

Related Accessibility rules

Data tables declare header cells

How this rule is weighted

Questions about this rule

Tags

Related Accessibility rules