v136 · css
Migration Calculator
Chrome 136 deprecates the UA stylesheet special rules that shrink <h1> inside <article>, <aside>, <nav>, <section>. Paste your HTML — the calculator shows the old computed font sizes, the new sizes after deprecation, and generates the CSS you need to preserve the old appearance.
checking H1 nesting behaviour…
The old UA stylesheet rule:
h1 inside one level of sectioning got 1.5em, two levels 1.17em, three levels 1em, four+ levels 0.83em. Chrome 136 removes this — all h1 elements get a flat 2em regardless of nesting. Authors who relied on the shrinking must add their own CSS.
Paste HTML to analyse
Font size impact table
| Nesting context | Old size (UA rule) | New size (Chrome 136) | CSS fix to preserve old size |
|---|---|---|---|
| Paste HTML and click Analyze. | |||
Visual comparison
Before (pre-Chrome 136)
After (Chrome 136+)
Generated migration CSS
Analyze HTML to generate migration CSS.