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Length conversion calculator
Use this tool to compare drawing dimensions and shop measuring systems. Conversion does not change a tolerance requirement or imply that a converted value has additional measurement accuracy.
Formula and inputs
1 inch = 25.4 mm; 1 foot = 304.8 mm.
Worked example
25.4 mm equals exactly 1 inch.
Use the result in your setup
Confirm the input dimensions and unit system against your drawing before calculating. Keep full precision during a calculation and round only the final value to suit the measurement or programming requirement. A numerical result does not account for a machine’s complete setup, workholding or control configuration.