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Converter Tools

REM to PX Converter

Enter REM values and get the equivalent pixel values instantly. Set any base font size — default 16px — and convert single values or a bulk list at once.

Last updated: May 21, 2026

Client-Side Processing
Input Data Stays on Device
Instant Local Execution

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What is REM to PX Converter?

REM (Root EM) is a CSS unit relative to the root element's font size. Browsers default the root font size to 16px, so 1rem = 16px. Converting REM back to px is useful when reading CSS from a design system or debugging computed sizes in browser DevTools.

The formula is: **px = rem × base font size**. So 1.5rem at a 16px base = 24px.

How to Use REM to PX Converter

1

Enter one or more REM values in the input box (comma or newline separated)

2

Set the base font size if your project uses a non-default value

3

Copy individual results or the full output

4

Use the reference table for common REM to px lookups

Common Use Cases

  • Developers reading CSS values in rem and translating them back to pixels for design review.
  • Front-end engineers debugging computed sizes that DevTools shows in px but the source is rem.
  • Teams migrating designs from rem back to px for a pixel-exact handoff.
  • Developers using a 10px base (html { font-size: 62.5% }) checking the px equivalent.
  • Students learning CSS unit relationships between px and rem.
  • Designers converting rem spacing tokens back to pixel values for design documentation.

Example Input and Output

Convert common REM values back to pixels at the default 16px base.

REM values
1
1.5
2
3
PX output
1rem → 16px
1.5rem → 24px
2rem → 32px
3rem → 48px

Privacy

All conversions run in your browser. No data is sent to any server.

Frequently Asked Questions

What base font size should I use?
Use the root font size set in your CSS. If you haven't changed it, leave it at 16px — the browser default. If you use the 62.5% trick (html { font-size: 62.5% }), set the base to 10.
What does DevTools show for rem-based values?
Browser DevTools shows computed pixel values, not rem values. This tool helps you reverse-engineer what rem value produced a specific px size you see in DevTools.
Is REM the same as EM?
No. REM is always relative to the root (html) element's font size. EM is relative to the current element's parent font size, which can cascade and compound. REM is more predictable for layout and typography.

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