Social & sharing
How to add a favicon
What 13x checks
This is rule social.favicon in the public registry: Favicon exists. It runs on every audit, against the pages we actually fetched, and its result is derived from the response rather than estimated.
- Surface
- Social & sharing
- Score weight
- 4 of the readiness score
- Scope
- Runs on every audited page
- Applies
- To every site
Registry version 2026-07-30. Every rule is published, and the audit is deterministic — the same page produces the same finding every time.
The fix
The same text the audit hands you when this check fails on your own site.
Add an SVG favicon with a PNG fallback:
<link rel="icon" href="/favicon.ico" sizes="32x32" />
<link rel="icon" href="/icon.svg" type="image/svg+xml" />Design it to read at 16px. A full logo becomes a grey smudge; a single letter or mark works.
Framework-specific versions
Where the change differs enough to be worth writing out separately.
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