About This Millimeters to Centimeters Converter
The millimeter (mm) and centimeter (cm) are adjacent metric units in the SI system — 10 millimeters equal exactly 1 centimeter. This is the simplest metric conversion: divide by 10 to go from mm to cm, multiply by 10 to go the other way. Every ruler, technical drawing, and measuring tape uses both units, and the relationship never changes. 1 mm = 0.1 cm; 1 cm = 10 mm.
This converter also handles meters, inches, feet, and yards. Precision engineers and machinists who work in millimeters but communicate dimensions in centimeters, students recording lab measurements, and product designers specifying small component sizes all convert between mm and cm as part of their normal workflow.
How to Use This Converter
- Enter the millimeter value in the Value field.
- Confirm Millimeter is selected in the From dropdown.
- Select Centimeter in the To dropdown (or any other unit).
- The result and formula appear instantly below.
- Use Swap to convert centimeters back to millimeters, or Reset to return to the default.
Units Covered
| Unit | Symbol | Common Use |
|---|---|---|
| Millimeter | mm | Engineering tolerances, precision parts, rainfall, jewelry sizing |
| Centimeter | cm | Body measurements, clothing sizes, product dimensions, rulers |
| Meter | m | Room dimensions, athletic distances, structural engineering |
| Inch | in | Screen sizes, US hardware and product dimensions |
| Foot | ft | Room heights, construction layouts, human height in US/UK |
| Yard | yd | Fabric and textile, outdoor distances |
Millimeters to Centimeters Conversion Table
| Millimeters [mm] | Centimeters [cm] |
|---|---|
| 1 mm | 0.1 cm |
| 5 mm | 0.5 cm |
| 10 mm | 1 cm |
| 20 mm | 2 cm |
| 25 mm | 2.5 cm |
| 50 mm | 5 cm |
| 75 mm | 7.5 cm |
| 100 mm | 10 cm |
| 150 mm | 15 cm |
| 200 mm | 20 cm |
| 250 mm | 25 cm |
| 300 mm | 30 cm |
How to Convert Millimeters to Centimeters
To convert millimeters to centimeters, divide by 10:
Example: Convert 85 mm to cm:
To convert centimeters back to millimeters, multiply by 10:
Example: Convert 4.5 cm to mm:
When You Need to Convert Millimeters to Centimeters
Rainfall measurements are one of the most common everyday triggers. Weather reports and rain gauges measure precipitation in millimeters — 12 mm of rain overnight, 85 mm for the month. Meteorology data and irrigation planning often reference monthly totals in centimeters. A farmer checking whether 85 mm of monthly rainfall meets the 8.5 cm irrigation threshold reads these as identical — but the unit on the gauge and the unit in the crop guide may differ. Agronomists, gardeners, and outdoor event planners convert between mm and cm for weather-related decisions daily.
Ring and jewelry sizing is almost entirely in millimeters, while product descriptions often use centimeters. A ring measured at 17 mm inner diameter corresponds to a 1.7 cm opening. Chain necklaces sold as "45 cm" need to be verified against clasp fitting dimensions quoted in millimeters. Jewelers measuring custom settings, gem certificates reporting stone dimensions in mm, and customers comparing product listings across formats all rely on this conversion for accuracy.
Technical product sheets in manufacturing frequently mix both units on the same page. A component drawing may label a bolt hole at 6 mm diameter within a bracket described as 8.5 cm wide. Quality inspectors verifying parts against specs, procurement teams comparing supplier datasheets, and assembly technicians cross-referencing installation guides all need quick mm-to-cm conversion to confirm measurements without error.