Unit Converter
Convert between length, weight, temperature, volume, area, speed, data size, and time units. Enter one value and see equivalents in every supported unit at once. Runs entirely in your browser — no uploads.
How to use
Pick a category (length / weight / temperature / volume / area / speed / data size / time), choose the input unit, and enter a number. All other units in the same category are computed instantly. Example: enter `1 mi` in length and you'll see km, m, ft, yd, etc. all at once. Data size supports both SI (1000-based) and IEC (1024-based) prefixes. Temperature uses the proper affine formulas (C ↔ F ↔ K). Everything runs in your browser — your value is never uploaded.
FAQ
- Is my input uploaded?
- No. Calculations run as plain JavaScript arithmetic in your browser; nothing is sent anywhere.
- Which categories and units are supported?
- Eight categories: length (mm/cm/m/km/in/ft/yd/mi/nmi), weight (mg/g/kg/t/oz/lb/st), temperature (°C/°F/K), volume (mL/L/m³/tsp/tbsp/fl oz/cup/pt/qt/US-gal/UK-gal), area (cm²/m²/km²/in²/ft²/yd²/acre/ha/tsubo), speed (m/s/km/h/mph/ft/s/knot/Mach), data size (bit/B/KB/MB/GB/TB/KiB/MiB/GiB/TiB), time (ms/s/min/h/d/w/month/year).
- What's the difference between KB and KiB?
- KB / MB / GB are SI prefixes (1000-based: 1 KB = 1000 B), while KiB / MiB / GiB are IEC prefixes (1024-based: 1 KiB = 1024 B). Operating systems differ on which they use, so both are listed.
- Temperature conversions are not simple ratios, right?
- Right. Celsius ↔ Fahrenheit ↔ Kelvin uses affine formulas (F = C × 1.8 + 32, K = C + 273.15). The tool first converts the input to Celsius and then to every other unit, which minimises rounding error.
- Why are months and years labelled "average"?
- Months are 28–31 days in the Gregorian calendar and years include leap years, so there's no single exact value in seconds. We use an average month of 30.4375 days and an average year of 365.25 days. Use the date-diff or business-day tools for calendar-exact math.
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