How accurate is the conversion?

All conversions use exact SI definitions: 1 inch = 2.54 cm exactly, 1 foot = 0.3048 m exactly, 1 mile = 1609.344 m exactly. Astronomical units use IAU 2015 definitions: 1 AU = 149,597,870,700 m, 1 ly = 9,460,730,472,580,800 m, 1 parsec = 3.0856775814913673e16 m.

What extras does this tool have?

Extras: (1) 18+ units across 5 systems, (2) Bidirectional single-unit conversion, (3) All-units-at-once table view, (4) Custom precision (0-10 decimals), (5) Scientific notation toggle for very large/small values, (6) Common conversions quick-reference (1 m = ? in every unit), (7) Convert chained units (e.g. 5 km 300 m 50 cm), (8) Decimal ↔ fraction display for imperial, (9) Copy individual results, (10) CSV export of all-unit view, (11) Temperature-style step ladder (e.g. powers of 10), (12) Conversion history (localStorage), (13) Add custom conversion factor.

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Length / Distance Unit Converter

Convert between 18+ length units: metric (m, km, cm, mm, µm, nm), imperial (in, ft, yd, mi, nautical mi), astronomical (AU, ly, parsec), typographic (pt, px), and more. With 10+ extras. 100% private.

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Value

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Precision (0-10)

Force scientific notationShow all-unit table

Chained length parser (e.g. "5 km 300 m 50 cm")

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How to use

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