Unit Converters.
Instant & Accurate.
Temperature, length, weight, area, volume, speed, time, and digital storage converters — all instant, all free, no signup required.
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Choose what you need to convert
Physical Units
Temperature, length, weight, area, volume, speed, time
Temperature Converter
PopularConvert between Celsius, Fahrenheit, and Kelvin instantly.
Length Converter
PopularConvert between meters, feet, inches, miles, kilometers, and more.
Weight Converter
PopularConvert between kilograms, pounds, ounces, grams, stones, and more.
Area Converter
Convert between square meters, square feet, acres, hectares, and more.
Volume Converter
Convert between liters, gallons, cups, fluid ounces, and more.
Speed Converter
Convert between mph, kph, knots, and meters per second.
Time Converter
Convert between seconds, minutes, hours, days, weeks, months, years.
Digital Storage
Bytes, KB, MB, GB, TB, PB and beyond
Free Unit Converters Online
Roughtools unit converters handle everything from everyday conversions (Celsius to Fahrenheit, kg to lbs) to specialist uses (knots to mph, hectares to acres). All conversions are instant, accurate to 6 significant figures, and run entirely in your browser.
No daily limits, no forced signups, no data sent to any server.
Why Roughtools Converters?
- ✓Temperature: Celsius, Fahrenheit, Kelvin with instant two-way conversion
- ✓Length: meters, feet, inches, miles, km, yards, nautical miles
- ✓Weight: kilograms, pounds, ounces, grams, stones, metric tons
- ✓Area, volume, speed, time, and digital storage — all in one place
- ✓Results accurate to 6 significant figures, no rounding errors
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