Online px to rem converter with custom root font-size and a common font-size quick table. A must-have for responsive layout work. Local computation.
TL;DR: px to rem both ways: custom root font-size and a common-sizes quick table.
This tool runs entirely in your browser. Open DevTools → Network panel and search your input — it appears in no request.
FAQ
Rule of thumb: font sizes in rem (follows user browser settings, accessibility-friendly), borders in px (a 1px divider should not thicken with font size), spacing per team convention.
Every rem value recalculates against the new base. Most browsers default to 16px; change it here if your design uses a different base.
16px by default. This tool recalculates live with a custom base.
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