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Area Unit Converter: mm², cm², in²
Type a value in any box and the others update. For a ram area, a stress area or a dolly face given in in² when your calculation uses mm² (or the other way round).
Area
1 in² = 645.16 mm² exactly; 1 cm² = 100 mm². Nothing you type is uploaded or saved.
mm² to in² table
| mm² | cm² | in² |
|---|
| 10 mm² | 0.10 cm² | 0.0155 in² |
| 20 mm² | 0.20 cm² | 0.0310 in² |
| 50 mm² | 0.50 cm² | 0.0775 in² |
| 100 mm² | 1.00 cm² | 0.1550 in² |
| 150 mm² | 1.50 cm² | 0.2325 in² |
| 200 mm² | 2.00 cm² | 0.3100 in² |
| 300 mm² | 3.00 cm² | 0.4650 in² |
| 500 mm² | 5.00 cm² | 0.7750 in² |
| 1,000 mm² | 10.00 cm² | 1.5500 in² |
| 2,000 mm² | 20.00 cm² | 3.1000 in² |
| 5,000 mm² | 50.00 cm² | 7.7500 in² |
in² to mm² table
| in² | mm² | cm² |
|---|
| 0.1 in² | 64.5 mm² | 0.65 cm² |
| 0.25 in² | 161.3 mm² | 1.61 cm² |
| 0.5 in² | 322.6 mm² | 3.23 cm² |
| 1 in² | 645.2 mm² | 6.45 cm² |
| 1.5 in² | 967.7 mm² | 9.68 cm² |
| 2 in² | 1,290.3 mm² | 12.90 cm² |
| 2.5 in² | 1,612.9 mm² | 16.13 cm² |
| 3 in² | 1,935.5 mm² | 19.35 cm² |
| 4 in² | 2,580.6 mm² | 25.81 cm² |
| 5 in² | 3,225.8 mm² | 32.26 cm² |
| 10 in² | 6,451.6 mm² | 64.52 cm² |
The conversion factors
The inch is defined as exactly 25.4 mm, so 1 in² = 25.4² = 645.16 mm² exactly, 1 mm² = 0.0015500031 in², 1 cm² = 100 mm² and 1 m² = 1,000,000 mm². Every factor is exact and the only rounding is in the display: the mm² table is rounded to 0.01 cm² and 0.0001 in², the in² table to 0.1 mm² and 0.01 cm²; the converter shows up to eight decimals.
Areas show up in pull testing as a hydraulic ram's effective area, a bolt's tensile stress area and a pull-off dolly's face. This page converts units only. To work out a ram area from its diameters, use the hydraulic ram effective area calculator; to turn a gauge reading into load, the gauge pressure to load calculator; for a bolt's stress area, the bolt tensile stress area calculator; for stress units, the stress unit converter.
Record the results in the full report workbook
The Fastener & Anchor Pull-Test Report Templates pack has a 40-row proof-test report with automatic PASS/FAIL, ultimate-load statistics, a calibration log, a unit converter, a printable procedure checklist and a standards index. $49 one-time, from Quality Tester Solutions LLC, the company behind Force-Test pull testers.