CSS units·36px
36px =
2.25rem
27pt

36 px in rem — 2.25 rem, 27 pt

36 px is 2.25 rem and 27 pt — 0.375 inches, 9.525 mm, and 225% of the root font size.

rem (root 16 px)
2.25rem
pt (points)
27pt · exact
pc (picas)
2.25pc
percent of root
225%
inches
0.375in
millimetres
9.525mm
centimetres
0.9525cm

Why rem divides by 16

Because browsers default the root font size to 16 px, and rem is a multiple of it. When a reader enlarges text in their browser settings, only the parts written in rem grow — anything pinned in px stays put.

Nearby sizes

pxrem (root 16 px)pt (points)
33px2.0625rem24.75pt
34px2.125rem25.5pt
35px2.1875rem26.25pt
36px2.25rem27pt
37px2.3125rem27.75pt
38px2.375rem28.5pt
39px2.4375rem29.25pt

On screen, pt and inches are still pixels

CSS fixes one inch at 96 px and one point at 1/72 inch. So 16 px is exactly 12 pt — but hold a ruler to the screen and that "inch" will not measure an inch.

Sizes you meet most

Body text at 16, small text at 14, spacing at 8, 24 and 32 — the values that keep coming back.

How to read this

  • rem = px ÷ 16, because browsers default the root font size to 16 px.
  • pt = px × 0.75, since CSS fixes an inch at 96 px and a point at 1/72 inch.
  • One pc is 12 pt, and one inch is both 96 px and 72 pt.
  • Use rem for text and spacing; keep px for hairlines such as borders.

Frequently asked questions

Q. How many rem is 36 px?

2.25 rem — that is 36 divided by 16.

Q. How many points is 36 px?

27 pt. A point is 1/72 inch and an inch is 96 px, so you multiply by 0.75.

Q. What length is that?

0.375 inches, or 9.525 mm — though a ruler on the screen will not agree.

Q. And as a percentage?

225% of the root font size.