CSS units·135px
135px =
8.4375rem
101.25pt

135 px in rem — 8.4375 rem, 101.25 pt

135 px is 8.4375 rem and 101.25 pt — 1.40625 inches, 35.719 mm, and 843.75% of the root font size.

rem (root 16 px)
8.4375rem
pt (points)
101.25pt
pc (picas)
8.4375pc
percent of root
843.75%
inches
1.40625in
millimetres
35.719mm
centimetres
3.5719cm

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)
132px8.25rem99pt
133px8.3125rem99.75pt
134px8.375rem100.5pt
135px8.4375rem101.25pt
136px8.5rem102pt
137px8.5625rem102.75pt
138px8.625rem103.5pt

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 135 px?

8.4375 rem — that is 135 divided by 16.

Q. How many points is 135 px?

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

Q. What length is that?

1.40625 inches, or 35.719 mm — though a ruler on the screen will not agree.

Q. And as a percentage?

843.75% of the root font size.