Engineering Design Tables

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VERIFIED TABLE

Exact engineering length conversions

Exact SI and inch/foot conversion factors used by the Length Unit Converter.

QuantityExact relationshipDecimal conversion
metre to millimetre1 m = 1000 mm1000 mm
inch to millimetre1 in = 25.4 mm25.4 mm
foot to millimetre1 ft = 12 in304.8 mm

Source: NIST Special Publication 811, Guide for the Use of the International System of Units (SI).

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