Unit Converter

Supported conversions

This converter covers the three unit categories people need most often: length (millimeters to miles), weight (grams to pounds), and temperature (Celsius, Fahrenheit and Kelvin). Length and weight conversions use precise multiplicative factors based on a common base unit (meters and kilograms respectively), while temperature uses the correct additive formulas since Celsius, Fahrenheit and Kelvin scales don't share a common zero point.

Quick reference

• 1 inch = 2.54 centimeters
• 1 mile = 1.60934 kilometers
• 1 pound = 0.453592 kilograms
• °F = (°C × 9/5) + 32

Frequently asked questions

How precise are the conversion results?

Conversions use standard, internationally recognized conversion factors (e.g. 1 inch = 2.54 cm exactly) and display results rounded to a sensible number of decimal places for readability, while calculating internally with full precision.

Why do some conversions like temperature need a formula instead of a simple multiplier?

Length, weight and volume conversions are proportional (multiply by a fixed factor), but temperature scales like Celsius and Fahrenheit have different zero points, so converting between them requires both a multiplication and an addition/subtraction step, not a single ratio.

Can I convert between any two units, or only within the same category?

You can convert between any two units within the same category - for example, between different length units, or between different weight units - but not across categories, since converting, say, meters to kilograms isn't mathematically meaningful.