Relative units let text and spacing scale when users change their browser font size, which helps accessibility. With the default 16 px base, 24 px is 1.5 em, 12 px is 0.75 em.
How to use the PX to EM Converter
- Base font size
- Pixels
- Every result field is editable: type into em / rem or any other result and Pixels plus every other field update to match.
Results update as you type, and every field accepts the units shown in its menu.
How it works
Pixels are divided by the base font size. Type an em value into the result to get pixels.
Common sizes (16 px base)
| px | em/rem | pt |
|---|---|---|
| 10 | 0.625 | 7.5 |
| 12 | 0.75 | 9 |
| 13 | 0.8125 | 9.75 |
| 14 | 0.875 | 10.5 |
| 15 | 0.9375 | 11.25 |
| 16 | 1 | 12 |
| 18 | 1.125 | 13.5 |
| 20 | 1.25 | 15 |
| 24 | 1.5 | 18 |
| 28 | 1.75 | 21 |
| 32 | 2 | 24 |
| 36 | 2.25 | 27 |
| 40 | 2.5 | 30 |
| 48 | 3 | 36 |
| 64 | 4 | 48 |
Inputs explained
| Field | What to enter |
|---|---|
| Base font size | In px |
| Pixels | In px |
What each result means
- em / rem = [Pixels] ÷ [Base font size]
- Points = [Pixels] × 0.75
- Percent = [Pixels] ÷ [Base font size] × 100
Formula
em = px ÷ base font size (px)Worked example
Inputs — Base font size: 16 px; Pixels: 24 px.
Results — em / rem = 1.5 em; Points = 18 pt; Percent = 150 %.
Frequently asked questions
What is 1 em in pixels?
16 px with the default base size.
What is the difference between em and rem?
rem is relative to the root (html) font size; em is relative to the parent element.
What formula does the PX to EM Converter use?
em = px ÷ base font size (px).