calc()

All browsers support calc() unprefixed, but do note that it can have a big impact on the layout and the consequent breaking of your design on unsupported browsers.

Verdict

Safe to use

Category

CSS features

Browser support

Can I Use

Works in

all modern browsers

Should you use calc() in 2026?

You should use it with a fallback declaration, so it doesn't break on browsers which don't support it.

width: 500px; / older browsers / width: calc(50% - 20px);

How to use it

.main { width: calc(100% - 240px); }   /* full width minus a sidebar */
.hero { min-height: calc(100vh - 64px); }

Polyfills and fallbacks

Progressive enhancement works well here: browsers without support degrade gracefully, so a dedicated polyfill is usually unnecessary.

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