Measurement & Conversion
Need to switch between metric centimeters and imperial inches for crafting, woodworking, school assignments, or international shopping? This guide covers the mathematical relationship, fractional subdivisions, and how to measure real items on your display.
Access our browser ruler tool to measure any physical object against your screen edge in either centimeters or fractional inches.
| Everyday Example | |||
|---|---|---|---|
| 1/4 in (0.25 in) | 0.635 cm | 6.35 mm | |
| 1/2 in (0.50 in) | 1.27 cm | 12.7 mm | |
| 1 in (1.00 in) | 2.54 cm | 25.4 mm | |
| 2 in (2.00 in) | 5.08 cm | 50.8 mm | |
| 3.37 in (3 3/8 in) | 8.56 cm | 85.6 mm | |
| 6 in (6.00 in) | 15.24 cm | 152.4 mm | |
| 12 in (1 foot) | 30.48 cm | 304.8 mm |
By international agreement adopted in 1959, exactly 1 inch is defined as 2.54 centimeters (or 25.4 millimeters). This conversion factor is exact and has no recurring decimals.
Multiply the measurement in inches by 2.54. For instance, a 6-inch photograph corresponds to 6 × 2.54 = 15.24 cm. Conversely, divide centimeters by 2.54 to convert back to inches.
Imperial ruler scales subdivide each inch into halves (1/2"), quarters (1/4"), eighths (1/8"), and sixteenths (1/16"). The tallest tick between whole numbers marks 1/2 inch, medium ticks mark 1/4 and 3/4 inches, and the smallest markings represent 1/16-inch increments.
Yes. On Easy Online Ruler, you can toggle between imperial inches, centimeters, and millimeters using keyboard shortcuts (1 for cm, 2 for inches, 3 for mm) or the toolbar switcher. Dragging a span across the screen displays live conversions simultaneously.
