PX to REM Converter
Convert pixels, rem and em instantly, then browse a practical CSS lookup table.
Lookup table
1px = 0.0625rem 2px = 0.125rem 3px = 0.1875rem 4px = 0.25rem 5px = 0.3125rem 6px = 0.375rem 7px = 0.4375rem 8px = 0.5rem 9px = 0.5625rem 10px = 0.625rem 11px = 0.6875rem 12px = 0.75rem 13px = 0.8125rem 14px = 0.875rem 15px = 0.9375rem 16px = 1rem 17px = 1.0625rem 18px = 1.125rem 19px = 1.1875rem 20px = 1.25rem 21px = 1.3125rem 22px = 1.375rem 23px = 1.4375rem 24px = 1.5rem 25px = 1.5625rem 26px = 1.625rem 27px = 1.6875rem 28px = 1.75rem 29px = 1.8125rem 30px = 1.875rem 31px = 1.9375rem 32px = 2rem 33px = 2.0625rem 34px = 2.125rem 35px = 2.1875rem 36px = 2.25rem 37px = 2.3125rem 38px = 2.375rem 39px = 2.4375rem 40px = 2.5rem 41px = 2.5625rem 42px = 2.625rem 43px = 2.6875rem 44px = 2.75rem 45px = 2.8125rem 46px = 2.875rem 47px = 2.9375rem 48px = 3rem 49px = 3.0625rem 50px = 3.125rem 51px = 3.1875rem 52px = 3.25rem 53px = 3.3125rem 54px = 3.375rem 55px = 3.4375rem 56px = 3.5rem 57px = 3.5625rem 58px = 3.625rem 59px = 3.6875rem 60px = 3.75rem 61px = 3.8125rem 62px = 3.875rem 63px = 3.9375rem 64px = 4rem
How to use
- Enter a value and choose its unit.
- Set the base font size used by your project.
- Use the result or copy the lookup table.
About this tool
Pixels are useful for measuring a design, while rem and em units make a CSS system more adaptable. This converter provides a quick, bidirectional reference between those units. REM is calculated from the document root font size: a value of 16 pixels means 1rem by default, while 24px becomes 1.5rem. EM uses the same mathematical relationship in this tool, but in a browser an em can inherit from the current element and therefore depends on context. Change the base font size whenever your project uses a different root size, such as 10px for a simplified mental scale or a user-adjustable accessibility setting. The lookup table covers common values from 1 to 64 pixels so you can scan a design system without repeating arithmetic. Results are rounded to four decimals to remain practical in CSS while preserving useful precision. When converting back from rem, multiply by the selected base instead of assuming 16px. Keep unit choices consistent within a component: rem is often ideal for spacing and typography that should respond to the root scale, while em can be useful for component-local relationships. This page performs all calculations in your browser, making it suitable for quick design checks without uploading source files or project data.
Frequently asked questions
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