10px to em
10px = 0.625em
At the browser default font size of 16 px. Change it and this number changes — see below.
How it is calculated
One px is 0.0625em, so:
10px × 0.0625 = 0.625emReversing it, 0.625em × 16 returns 10px.
10px at other font sizes
em is measured against the element's own font size, inherited from its parent unless it sets one, so the answer above holds only while that is 16 px. Nested elements each compound on their parent, so this is the value for one level, not for the whole tree.
| Font size | 10px equals |
|---|---|
| 14 px | 0.714286em |
| 16 px (default) | 0.625em |
| 18 px | 0.555556em |
| 20 px | 0.5em |
| 24 px | 0.416667em |
Nearby values
| px | em |
|---|---|
| 8px | 0.5em |
| 10px | 0.625em |
| 12px | 0.75em |
| 14px | 0.875em |
| 16px | 1em |
| 18px | 1.125em |
Frequently asked questions
What is 10px in em?
0.625em at the default 16 px font size.
How is 10px converted to em?
Multiply by 0.0625: 10 × 0.0625 = 0.625. To go back, multiply 0.625 by 16.
Is 0.625em always the answer?
No. em is relative to the element's own font size, inherited from its parent unless it sets one, so 10px is 0.625em only while that is 16 px. The table above gives the value at the sizes you are most likely to meet.