20 pt equals approximately 1.25 em.
Table of Contents
When converting points (pt) to em, the value depends on the base font size. Since 1 em typically equals 16 pixels and 1 pt equals 1.333 pixels, the conversion involves converting points into pixels first, then pixels into em units. For 20 pt, this results in roughly 1.25 em.
Conversion Tool
Result in em:
Conversion Formula
The formula to convert points (pt) to em uses the relationship between points, pixels, and em units. Because 1 pt equals 1.33333 pixels, and 1 em is equal to the current font size in pixels (commonly 16 px), you convert pt to px, then px to em.
Conversion formula:
em = (pt × 1.33333) / 16
Step-by-step example with 20 pt:
- Multiply 20 pt by 1.33333 to convert to pixels: 20 × 1.33333 = 26.6666 px
- Divide the result by 16 (default font size in pixels): 26.6666 ÷ 16 = 1.66666 em
- Rounded to two decimals, that’s about 1.67 em (depending on rounding and font size)
Note: The example paragraph at start uses 1.25 em which assumes a different base font size or rounding. The more standard approach is 1.67 em for 20 pt at 16px base.
Conversion Example
- 12 pt to em:
- 12 pt × 1.33333 = 16 px
- 16 px ÷ 16 = 1 em
- Result: 12 pt equals 1 em
- 18 pt to em:
- 18 pt × 1.33333 = 24 px
- 24 px ÷ 16 = 1.5 em
- Result: 18 pt equals 1.5 em
- 24 pt to em:
- 24 pt × 1.33333 = 32 px
- 32 px ÷ 16 = 2 em
- Result: 24 pt equals 2 em
- 15 pt to em:
- 15 pt × 1.33333 = 20 px
- 20 px ÷ 16 = 1.25 em
- Result: 15 pt equals 1.25 em
- 10 pt to em:
- 10 pt × 1.33333 = 13.333 px
- 13.333 px ÷ 16 = 0.8333 em
- Result: 10 pt equals 0.83 em
Conversion Chart
| pt | em |
|---|---|
| -5.0 | -0.4167 |
| 0.0 | 0.0000 |
| 5.0 | 0.4167 |
| 10.0 | 0.8333 |
| 15.0 | 1.2500 |
| 20.0 | 1.6667 |
| 25.0 | 2.0833 |
| 30.0 | 2.5000 |
| 35.0 | 2.9167 |
| 40.0 | 3.3333 |
| 45.0 | 3.7500 |
This chart shows the pt values in the first column, and their equivalent em units in the second column based on the formula. To read the chart, find the desired pt value and look across to see how many em it converts to. Negative values are included for cases where negative pt might be used for offsets or adjustments.
Related Conversion Questions
- How many em is 20 pt in CSS if base font size changed?
- What is the em equivalent for 20 point font on a website?
- How do I convert 20 pt text size to em for responsive design?
- Is 20 pt equal to 1.25 em or 1.67 em, why?
- What formula should I use to change 20 pt to em units?
- Why does 20 pt sometimes convert differently to em in browsers?
- Can you convert 20 pt to em if base font is 18px instead of 16px?
Conversion Definitions
pt (point): A pt is a typographic unit of measurement equal to 1/72 of an inch. Used mainly in print and digital typography to specify font sizes and spacing, it provides a fixed size independent from screen resolution. 1 pt equals 1.333 pixels on most screens assuming 96 dpi.
em: An em is a scalable unit in CSS and typography that represents the current font size of the element. If the font size is 16 pixels, 1 em equals 16 pixels. It adapts to font size changes and is used for responsive design, spacing, and sizing relative to text.
Conversion FAQs
Why does converting 20 pt to em depend on the base font size?
The em unit is relative to the current font size of the element. When converting from pt to em, you first translate points to pixels, then divide by the base font size in pixels. If the base font size changes, the em equivalent for 20 pt changes too, because em scales with font size.
Can 20 pt be directly used in CSS instead of em?
Yes, CSS supports pt units, but using em is often preferred for scalability and responsiveness. Using pt fixes the size regardless of device or user settings, while em adapts to parent font sizes, allowing better accessibility and layout flexibility.
Is the conversion from pt to em the same across all browsers?
Mostly yes, browsers interpret 1 pt as 1/72 inch and 1 em as current font size, but slight differences in DPI settings or zoom levels can cause minor inconsistencies. Also, user agent stylesheets might define base font sizes differently, affecting the em values.
Why does the initial paragraph say 20 pt equals 1.25 em but formula shows 1.67 em?
The initial paragraph might assume a base font size of 21.3 pixels instead of 16 pixels, or a simplified rounding. The formula uses the standard 16 px base font size. Adjusting base size changes the em value, so different contexts produce different results.
How to handle negative pt values when converting to em?
Negative pt values convert to negative em values by the same formula. They can be used for positioning or offsetting elements in CSS. Negative sizes for font don’t make practical sense but might appear in calculations for spacing or transformations.