Is 1rem equal to 12pt?

Only when the root size is 16 CSS px. At a 20px root, 1rem is 15 CSS pt; at a 10px root it is 7.5pt.

Does my monitor's DPI change the calculation?

No. This calculation uses the defined CSS relationship of 96px to 72pt per inch. It does not measure a physical display or printer.

Can this guarantee the size in a printed PDF?

No. It gives the CSS reference value. Check print scaling, fonts and export settings in the actual renderer.

Utill.net

REM to PT Converter — CSS & Print Reference

Convert rem to CSS points using your root font size and the 96px-per-inch rule. Check print styles with a live calculator, examples and rounding limits.

This conversion runs only in your browser — nothing is uploaded.

Value

Unit

Root / base font size

Root / base font size16px
Unitrem

em in real CSS follows the parent element's font-size; this tool approximates rem and em with the same root/base value.

When to use this

Translate a root-relative typography token into a CSS print-size reference.
Compare a point-based design handoff with the web's rem scale.
Inspect a print stylesheet before checking the actual PDF or printer output.

How the result is calculated

CSS defines 1in = 96px = 72pt, so one CSS pixel is 0.75pt. First multiply rem by the root size to get px; then multiply by 0.75. For example, 1.125rem at 16px gives 18px and 13.5pt. At a 20px root, 1rem gives 15pt instead of 12pt.

Open the full tool

Worked examples

Reference values below use the stated root size. The interactive tool above uses your current settings.

Root font size: 16px. Rounded display values; CSS px and pt are reference units, not a measurement of your screen's physical pixels.
Input	Result	What to check
0rem	0.00pt	16px root
0.0625rem	0.75pt	16px root
0.5rem	6.00pt	16px root
0.75rem	9.00pt	16px root
1rem	12.00pt	16px root
1.125rem	13.50pt	16px root
1.5rem	18.00pt	16px root
2rem	24.00pt	16px root
3rem	36.00pt	16px root

Practical pitfalls

The 96px relation is a CSS unit definition, not a statement that a screen has 96 physical pixels per inch. Do not substitute monitor DPI into this formula.
Print scaling, margins, font substitution and PDF rendering can change the final output. Compare print preview and an actual export.
The calculator displays pt to two decimal places. For 0.0625rem at 16px the exact value is 0.75pt; very small values may round to zero.

References

Last reviewed: 2026-10-11

Task guides with ready-to-use settings

PX to REM Converter — Custom Root Font Size
Divide the pixel value by the root font size: at a 16px root, 24px is 1.5rem. Set the calculator's base to your computed html font size; conversion runs in your browser.
REM to PX Converter — Check Computed Sizes
Multiply rem by the root font size: 1.5rem is 24px at a 16px root and 30px at a 20px root. Use your page's computed html font size. The calculator runs locally.

Browse all task guides

Frequently asked questions

Is 1rem equal to 12pt?: Only when the root size is 16 CSS px. At a 20px root, 1rem is 15 CSS pt; at a 10px root it is 7.5pt.
Does my monitor's DPI change the calculation?: No. This calculation uses the defined CSS relationship of 96px to 72pt per inch. It does not measure a physical display or printer.
Can this guarantee the size in a printed PDF?: No. It gives the CSS reference value. Check print scaling, fonts and export settings in the actual renderer.