20 pt equals 1.25 rem.
This conversion comes from the relationship between points and pixels, and pixels and rem units in CSS. Since 1 pt is 1.25 pixels and 1 rem is 16 pixels by default, dividing 25 pixels (20 pt × 1.25) by 16 gives the result in rem.
Conversion Tool
Result in rem:
Conversion Formula
The formula to convert points (pt) to rem units is:
rem = (pt × 1.25) ÷ 16
Why? CSS uses pixels as a base unit, where 1 pt equals 1.25 pixels, and rem is relative to the root font size (usually 16 pixels). So you convert pt to pixels first by multiplying by 1.25, then divide by 16 to get rem.
Example:
- Given 20 pt, multiply by 1.25 to get pixels: 20 × 1.25 = 25 px
- Divide pixels by 16 (root font size): 25 ÷ 16 = 1.5625 rem
- So 20 pt = 1.5625 rem
Conversion Example
- Convert 8 pt to rem:
- 8 × 1.25 = 10 px
- 10 ÷ 16 = 0.625 rem
- Convert 15 pt to rem:
- 15 × 1.25 = 18.75 px
- 18.75 ÷ 16 = 1.1719 rem
- Convert 30 pt to rem:
- 30 × 1.25 = 37.5 px
- 37.5 ÷ 16 = 2.3438 rem
- Convert 5 pt to rem:
- 5 × 1.25 = 6.25 px
- 6.25 ÷ 16 = 0.3906 rem
- Convert 12 pt to rem:
- 12 × 1.25 = 15 px
- 15 ÷ 16 = 0.9375 rem
Conversion Chart
| pt | rem |
|---|---|
| -5.0 | -0.3906 |
| 0.0 | 0.0000 |
| 5.0 | 0.3906 |
| 10.0 | 0.7813 |
| 15.0 | 1.1719 |
| 20.0 | 1.5625 |
| 25.0 | 1.9531 |
| 30.0 | 2.3438 |
| 35.0 | 2.7344 |
| 40.0 | 3.1250 |
| 45.0 | 3.5156 |
This chart helps you quickly find the rem value for standard pt sizes. Negative pt values shown for completeness but are rarely used. Each rem value is calculated by multiplying pt by 1.25, then dividing by 16.
Related Conversion Questions
- How many rem units is 20 pt in CSS font sizing?
- What’s the equivalent of 20 pt in rem for responsive design?
- Is 20 pt larger or smaller than 1 rem?
- How do I convert 20 pt to rem when the root font size is different?
- Can I use 20 pt directly in CSS instead of rem?
- Why does 20 pt equal 1.5625 rem in web design?
- What’s the formula to change 20 pt to rem units?
Conversion Definitions
pt: Pt stands for point, a unit of length used mainly in typography and printing. One point equals 1/72 of an inch, and in digital screens, it’s standardized to 1.25 pixels. Points are used to define font sizes, spacing, and other layout dimensions.
rem: Rem is a CSS unit called root em. It relative to the font size of the root element (html). If the root font size is 16 pixels, then 1 rem equals 16 pixels. Rem units allow scalable and consistent sizing across a webpage.
Conversion FAQs
Is the root font size always 16 pixels when converting pt to rem?
Not always. Browsers commonly set the root font size to 16 pixels, but users or developers can change it. Since rem is relative to that root size, conversions from pt to rem must consider actual root font size to be precise.
Why multiply pt by 1.25 before converting to rem?
Because 1 pt equals 1/72 inch and screens use pixels based on 96 dpi, 1 pt corresponds to 1.25 pixels (96 ÷ 72 = 1.3333, but CSS rounds to 1.25 for consistency). Multiplying pt by 1.25 converts points to pixels before converting pixels to rem.
Can I directly use pt units in CSS instead of rem?
You can use pt in CSS but it’s not recommended for responsive designs. Pt measures physical size, which might not scale well on different screens. Rem adapts to root font size, making it better for flexible layouts.
What happens if the root font size changes after I set rem values?
All rem-based sizes adjust automatically. If the root font size increases, elements sized in rem grow proportionally, which can affect layout and readability. This makes rem units useful for accessibility but means you must test changes carefully.
Are there any limitations converting pt to rem?
Yes, pt assumes fixed physical dimensions which don’t always match screens’ pixel density or user settings. Also, rem depends on root font size, which can vary. So conversions can be approximate, not exact across all devices.
