FilterableAll UnitsFree
px

Pixels. Fixed size, best for borders and shadows.

Absolute
em

Relative to parent font-size. Compounds with nesting.

Relative
rem

Relative to root font-size. Predictable scaling.

Relative
%

Relative to parent element size.

Relative
vw

1% of viewport width. Great for responsive layouts.

Viewport
vh

1% of viewport height. Full-height sections.

Viewport
vmin

1% of smaller viewport dimension.

Viewport
vmax

1% of larger viewport dimension.

Viewport
ch

Width of the "0" character. Ideal for max-width on text.

Relative
ex

Height of the "x" character in current font.

Relative
cm

Centimeters. Only for print stylesheets.

Absolute
mm

Millimeters. Only for print stylesheets.

Absolute
in

Inches. 1in = 96px. Print only.

Absolute
pt

Points. 1pt = 1/72 inch. Common in print.

Absolute
dvh

Dynamic viewport height. Accounts for mobile browser bars.

Viewport
svh

Small viewport height. Smallest possible viewport.

Viewport
lvh

Large viewport height. Largest possible viewport.

Viewport
cqi

Container query inline size. For container queries.

Container
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About CSS Units

CSS Units solves a specific problem that comes up daily for anyone dealing with developer and design work: doing it once, fast, without an account. Processing runs locally in your browser using modern Web APIs. Nothing is uploaded, nothing is logged, and there is no quota to worry about for casual use. It pairs naturally with the other developer utilities here when you need to chain a quick workflow.

When you'd reach for CSS Units

  • You need to handle a one-off task right before a meeting and don't have time to install anything.

    Anyone working remotely on a borrowed or restricted machine.

    Open the page, get the result, paste it into your doc — under a minute.

  • You're on a public or shared machine and don't want to leave traces of what you're working on.

    Travelers, contractors, anyone working from a friend's computer.

    Nothing is uploaded, nothing persists if you're not signed in.

  • You're cleaning up a folder of files that accumulated over a project and need to standardize them.

    Designers, writers, and developers wrapping up deliverables.

    Drop each file in, copy the output, move on.

  • You're hitting the daily limit of a paid SaaS and need a backup option for a single quick job.

    Marketers and ops people whose primary tool is metered.

    Stay productive without burning credits.

Frequently asked about CSS Units

Do I need to create an account to use CSS Units?
No. CSS Units works without any signup. We only ask for an email if you decide to subscribe to a paid plan.
Are my files uploaded to a server when I use CSS Units?
CSS Units processes everything in your browser using local APIs. Your files never leave your device.
Is CSS Units really free?
Yes — CSS Units is free for unlimited personal use, with no account required and no watermark on the output.
What browsers does CSS Units support?
Every modern browser released in the last three years: Chrome, Firefox, Safari, Edge, Brave, Opera.
Can I use CSS Units commercially?
Yes. The output of CSS Units belongs entirely to you, with no licensing restrictions.

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