Unit Converter: Convert Length, Weight & More

Choose the unit definition before converting

SimplyUtils converts length, weight (mass), temperature, volume, speed, area, data and fixed time durations. Choose a category, select the From unit and To unit, and enter a decimal value. The main output and the category's other conversions update immediately. Swap uses the displayed result as the new input, so repeated swaps may accumulate its rounding.

Worked examples across all eight categories

  • Length: 1 international foot is 0.3048 meters.
  • Weight: 1 avoirdupois pound is 0.45359237 kilograms.
  • Temperature: 0 Celsius is 32 Fahrenheit or 273.15 Kelvin.
  • Volume: 1 US gallon is 3.785411784 liters.
  • Speed: 60 miles per hour is 96.56064 kilometers per hour.
  • Area: 1 acre based on the international foot displays 4046.856422 square meters.
  • Data: 1 KB is 1,000 bytes; 1 KiB is 1,024 bytes.
  • Time: 1 hour is 3,600 seconds.

Definitions that prevent the wrong result

KB, MB, GB and TB use powers of 1,000. KiB, MiB, GiB and TiB use powers of 1,024; a byte is eight bits. For example, 1 MiB becomes 1.048576 MB. These follow the distinction documented by NIST's SI and binary-prefix guidance. The previous converter used the binary factor under decimal labels; the definitions are now distinct.

The gallon, fluid ounce, cup and tablespoon use US customary liquid measures. An imperial gallon or a 250 mL metric cup is a different unit and is not offered here. Foot, mile, square foot and acre use the international foot, not the former US survey foot. Pounds and ounces are avoirdupois mass, not troy measures or force. See NIST's conversion-factor reference for the underlying unit distinctions.

A day is a fixed 86,400-second duration, a week is seven such days, a year is 365 days and the month option is one twelfth of that year (2,628,000 seconds). These are duration conventions. They cannot locate next month on a calendar or count local clock hours across daylight-saving changes. Use the date calculator for date-only arithmetic.

Invalid inputs and precision

Enter a number without commas, currency signs or unit text; scientific notation such as 1e6 is accepted. Blank input clears the outputs. Invalid or overflowing values show an explanation and hide the copy controls. Temperatures below absolute zero are rejected. Negative values in other categories remain mathematical conversions rather than validation of a physical measurement.

Values use floating-point arithmetic and display up to 10 significant digits. Conversion does not know measurement uncertainty, significant figures in your source or the tolerance required by a project. Very small values may underflow to zero. Do not use the displayed digits as evidence of greater precision than the original measurement.

Processing and privacy

Unit calculations run in browser memory with no calculation API or saved history. Copy sends the displayed number to your clipboard. Switching categories resets the input to 1 and selects that category's initial pair. The Privacy Policy covers the site's general analytics.