CM to EM Converter
Use this free online cm to em converter tool to convert centimeters to em units. Centimeters are a metric absolute unit while EM is a scalable web unit based on parent font-size. Essential for converting metric print measurements to web design.
To convert centimeters to em, first convert to pixels (cm × 96 ÷ 2.54), then divide by the parent font-size. The default parent font-size is 16px. This bridges metric measurements with parent-relative web units.
Conversion Formula
em = (cm × 96 ÷ 2.54) ÷ parent font-size
For example, to convert 2.54cm (1 inch) to em with 16px parent font-size, calculate (2.54 × 96 ÷ 2.54) ÷ 16 = 6em. Similarly, 1.27cm equals 3em.
CM to EM Converter Conversion Table (Parent: 16px)
| CM | EM |
|---|---|
| 0.5cm | 1.181em |
| 1cm | 2.362em |
| 1.5cm | 3.543em |
| 2cm | 4.724em |
| 2.54cm | 6em |
| 3cm | 7.087em |
| 4cm | 9.449em |
| 5cm | 11.81em |
| 7.5cm | 17.72em |
| 10cm | 23.62em |
| 12.7cm | 30em |
| 15cm | 35.43em |
| 20cm | 47.24em |
| 25.4cm | 60em |
| 30cm | 70.87em |
What is CM?
Centimeters (cm) are an absolute CSS unit representing physical centimeters, commonly used in print design and international contexts. In web contexts, 1cm equals approximately 37.8 pixels. While uncommon for screen design, centimeters are valuable for print stylesheets where physical dimensions matter.
What is EM?
EM is a relative CSS unit that scales based on the parent element's font size, making it highly context-dependent. By default, 1em equals the parent element's font-size value, creating a cascading effect through nested elements. While EM offers flexibility for component-level scaling, its cascading nature can make it unpredictable compared to REM in complex layouts.