CM to REM Converter
Use this free online cm to rem converter tool to convert centimeters to root em units. Centimeters are a metric absolute unit while REM is a scalable web unit. This converter bridges metric print measurements with responsive web typography.
To convert centimeters to rem, first convert to pixels (cm × 96 ÷ 2.54), then divide by the root font-size. The default root font-size is 16px. This enables metric measurements to work with scalable web designs.
Conversion Formula
rem = (cm × 96 ÷ 2.54) ÷ root font-size
For example, to convert 2.54cm (1 inch) to rem with 16px root font-size, calculate (2.54 × 96 ÷ 2.54) ÷ 16 = 6rem. Similarly, 1.27cm equals 3rem.
CM to REM Converter Conversion Table (Root: 16px)
| CM | REM |
|---|---|
| 0.5cm | 1.181rem |
| 1cm | 2.362rem |
| 1.5cm | 3.543rem |
| 2cm | 4.724rem |
| 2.54cm | 6rem |
| 3cm | 7.087rem |
| 4cm | 9.449rem |
| 5cm | 11.81rem |
| 7.5cm | 17.72rem |
| 10cm | 23.62rem |
| 12.7cm | 30rem |
| 15cm | 35.43rem |
| 20cm | 47.24rem |
| 25.4cm | 60rem |
| 30cm | 70.87rem |
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 REM?
REM (Root EM) is a relative CSS unit based on the root element's font size, typically 16px by default in most browsers. Unlike EM units which cascade based on parent elements, REM provides consistent sizing throughout the document. This makes REM ideal for creating scalable, accessible designs that respect user font-size preferences.