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Results update instantly while you type.1 metre = 3.28084 feet y = x × 3.28084
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Built for serious conversion work
Massive standards libraryModern SI prefixes sit alongside practical, scientific, and historical units.
1,052 unitsEveryday measures through scientific and historical standards.
Expression inputFractions, arithmetic, exponents, π, e, and mixed numbers.
Correct conversion modelsLinear, offset, and reciprocal math covers temperature and fuel economy properly.
Shareable deep linksCategory, units, and value travel together in the URL.
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Accuracy and definitions
The converter uses double-precision floating-point arithmetic and standards-based factors. Exact definitions, including 1 inch = 25.4 mm, 1 international pound = 0.45359237 kg, and 1 byte = 8 bits, stay exact within the numeric engine. Display rounding never changes the underlying result.
Decimal vs binary dataKB means 1,000 bytes; KiB means 1,024 bytes. Both systems are kept separate.
Contextual unitsMach, sound speed, CSS pixels, tatami, and calendar averages show the assumption used.
Physical quantitiesMass and force, energy and torque, and absorbed and equivalent dose remain distinct.
FAQ
No. Every value is converted locally on your device, with a compatibility fallback for older browsers.
No. A kilobyte (KB) is 1,000 bytes under SI; a kibibyte (KiB) is 1,024 bytes under IEC. The converter includes both through the largest standardized prefixes.
Temperature scales use offsets as well as multipliers. Fuel economy uses reciprocal formulas, so MPG and L/100 km convert correctly instead of being treated as simple ratios.
Choose up to 15 significant digits when you need them, but measured input never becomes more accurate through conversion. Match the output precision to the precision of your source measurement.