px ⇔ rem/em Converter - CSS Unit Converter
Set base font size and convert between px/rem/em. Useful for responsive design CSS unit conversion.
px
px Result
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rem Result
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em Result
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Reference Table
| px | rem | em |
|---|---|---|
| 8px | 0.5rem | 0.5em |
| 10px | 0.625rem | 0.625em |
| 12px | 0.75rem | 0.75em |
| 14px | 0.875rem | 0.875em |
| 16px | 1rem | 1em |
| 18px | 1.125rem | 1.125em |
| 20px | 1.25rem | 1.25em |
| 24px | 1.5rem | 1.5em |
| 32px | 2rem | 2em |
| 48px | 3rem | 3em |
| 64px | 4rem | 4em |
How to Use
- Enter base font size (default 16px)
- Enter px value to convert to rem/em
- Enter rem/em to convert to px
FAQ
- Which units are supported?
- px, rem, em, vw, vh, and % are supported for mutual conversion.
- Can the base font size be changed?
- Yes. You can freely set the base font size used for rem/em calculations.
- Is my data sent to a server?
- No. All processing happens in your browser.
- How do I use this tool?
- Enter a value and its unit, and the tool will display the equivalent values in px, em, rem, vw, vh, and other units. You can also configure the base font size and viewport size.
- What reference value is used for vw and vh calculations?
- The viewport size can be configured in the tool. A default value is provided, but you can change it to match your actual screen dimensions for accurate results.
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Update History
Last Updated: 2026-02-21
- 2026-02-21 Initial release