18px to rem
18px = 1.125rem
At the browser default root font size of 16 px. Change it and this number changes — see below.
How it is calculated
One px is 0.0625rem, so:
18px × 0.0625 = 1.125remReversing it, 1.125rem × 16 returns 18px.
18px at other root font sizes
rem is measured against the root element, so the answer above holds only while that is 16 px. A visitor who has raised their browser's default — the accessibility setting rem exists to respect — is reading your page at one of the larger rows.
| Root font size | 18px equals |
|---|---|
| 14 px | 1.2857rem |
| 16 px (default) | 1.125rem |
| 18 px | 1rem |
| 20 px | 0.9rem |
| 24 px | 0.75rem |
Nearby values
| px | rem |
|---|---|
| 10px | 0.625rem |
| 12px | 0.75rem |
| 14px | 0.875rem |
| 16px | 1rem |
| 18px | 1.125rem |
| 20px | 1.25rem |
| 24px | 1.5rem |
Frequently asked questions
What is 18px in rem?
1.125rem at the default 16 px root font size.
How is 18px converted to rem?
Multiply by 0.0625: 18 × 0.0625 = 1.125. To go back, multiply 1.125 by 16.
Is 1.125rem always the answer?
No. rem is relative to the root element, so 18px is 1.125rem only while that is 16 px. The table above gives the value at the sizes you are most likely to meet.