Unit Converter

Convert between metric and imperial units for length, weight, temperature, and volume. Handy for travel, cooking, homework, and quick everyday checks.

Metric vs imperial

Most countries use the metric system (meters, kilograms, liters). The United States commonly uses feet, pounds, and gallons for daily life. Mixing systems without converting caused famous engineering mistakes—always label your units.

This converter is for general use. Medical, aviation, and legal applications may require stricter standards and certified tools.

What is unit conversion?

Unit conversion changes a measurement from one unit to another within the same dimension (length, weight, temperature, etc.) using fixed conversion factors.

This tool supports common metric and imperial units so you can translate recipes, travel distances, science homework, or product specs without manual lookup tables.

How the calculation works

  1. Select the measurement category (length, weight, temperature, etc.).
  2. Choose source and target units.
  3. Multiply by the conversion factor (or apply offset formulas for temperature).
  4. Display the converted value.

Worked examples

Miles to kilometers

  • 10 miles × 1.609344 = 16.09 km

Useful for road trip planning in countries using metric signs.

Celsius to Fahrenheit

  • 25 °C → (25 × 9/5) + 32 = 77 °F

Temperature conversions require an offset, not a simple multiplier.

Practical uses

  • Cooking and baking with international recipes
  • Science and engineering homework checks
  • Fitness (kg vs lb, km vs mi)

Limitations

  • !Rounding may differ slightly from other converters
  • !Does not convert between incompatible dimensions (length vs volume)

References

How This Converter Works

1

Choose a category

Length, weight, temperature, and volume each have their own unit lists.

2

Apply conversion factors

Most units convert through standard ratios; temperature uses dedicated formulas.

3

See the result

The output updates immediately—no button required after you enter a value.

What is Unit Converter?

A unit converter is a tool that translates a measurement from one unit into another within the same category, such as length, weight, temperature, or volume. It multiplies your value by a fixed conversion factor, so results are exact rather than estimated.

Select a measurement type, enter a number, and pick source and target units. Conversions use published conversion factors; temperature uses standard Celsius, Fahrenheit, and Kelvin formulas.

Four categories

Length, weight, temperature, and volume in one place.

Private

Calculations run locally—nothing is uploaded.

Quick checks

For precise science or trade, verify with official references.

Last updated: · Published:

How to Use This Tool

1

Pick a category

Choose length, weight, temperature, or volume.

2

Enter a value

Type the number you want to convert.

3

Select units

Set the from and to units in the dropdowns.

4

Read the result

The converted value updates as you change inputs.

Pro Tips

  • Double-check unit names—teaspoons and tablespoons differ from milliliters by region
  • For recipes, weigh ingredients when precision matters
  • Use Kelvin for science; Celsius and Fahrenheit for everyday weather
  • When traveling, convert fuel economy and speed limits carefully (miles vs kilometers)
  • Keep original measurements on engineering drawings—convert only for display

Frequently Asked Questions

Which unit categories does this tool support?
You can convert length (meters, feet, miles, etc.), weight (kilograms, pounds, ounces, etc.), temperature (Celsius, Fahrenheit, Kelvin), and volume (liters, gallons, cups, etc.). Pick a category, then choose from and to units.
How are temperature conversions handled?
Temperature uses proper formulas—not a simple multiplier. Celsius, Fahrenheit, and Kelvin convert through standard offset and scaling rules so freezing and boiling points stay accurate.
How precise are the results?
Results show several decimal places for everyday and light technical use. For legal or scientific work, confirm critical values against an official reference such as NIST.
Is my input sent to a server?
No. Conversions run entirely in your browser. Nothing you type is stored or transmitted.
Why do US and UK units sometimes differ?
Some names overlap but sizes differ—for example US gallons vs UK imperial gallons, or short tons vs metric tons. This tool uses the conversion factors built into each unit definition in the selector.
Can I convert compound units like miles per hour?
Not in this version. It converts single quantities within one category at a time (e.g., miles to kilometers, not mph to km/h directly).