CSS units·108px
108px =
6.75rem
81pt

108 px in rem — 6.75 rem, 81 pt

108 px is 6.75 rem and 81 pt — 1.125 inches, 28.575 mm, and 675% of the root font size.

rem (root 16 px)
6.75rem
pt (points)
81pt · exact
pc (picas)
6.75pc
percent of root
675%
inches
1.125in
millimetres
28.575mm
centimetres
2.8575cm

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)
105px6.5625rem78.75pt
106px6.625rem79.5pt
107px6.6875rem80.25pt
108px6.75rem81pt
109px6.8125rem81.75pt
110px6.875rem82.5pt
111px6.9375rem83.25pt

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 108 px?

6.75 rem — that is 108 divided by 16.

Q. How many points is 108 px?

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

Q. What length is that?

1.125 inches, or 28.575 mm — though a ruler on the screen will not agree.

Q. And as a percentage?

675% of the root font size.