Why doesn't temperature show a conversion factor like the others?

Temperature scales don't convert by multiplication alone, they also have an offset. Fahrenheit to Celsius needs (°F − 32) × 5/9, so the tool shows the exact formula used instead of a single factor.

How precise are the conversions?

Factors use full-precision definitions (for example, 1 inch = 0.0254 meters exactly). Results are rounded to 10 significant digits for display.

Can I convert negative numbers?

Only for temperature, where negatives are meaningful (below freezing). Length, weight, and volume accept zero and positive values.

Unit Converter

Convert length, weight, temperature, and volume between US and metric units.

Value

From

1 mi = 1.609344 km

Conversion used: 1 mi = 1.609344 km

US customary units are listed first. Gallons, quarts, pints, and fluid ounces use the US liquid definitions. Temperature conversions use exact formulas rather than a single factor. Data storage uses decimal SI units (1 KB = 1,000 bytes). All math happens in your browser; nothing is sent or stored.

About this tool

The unit converter switches between US customary and metric units for length, weight, temperature, and volume. Miles, feet, pounds, gallons, and Fahrenheit sit alongside kilometers, meters, kilograms, liters, and Celsius, with US units listed first since that's what most American shoppers, cooks, and travelers reach for. Pick a tab, type a value, choose your units, and the answer appears instantly.

What sets this converter apart is transparency: every result shows the exact conversion factor it used, like 1 mi = 1.609344 km. Temperature conversions use the correct formulas with their offsets rather than a misleading single multiplier. The math uses full-precision definitions, an inch is exactly 0.0254 meters, a US liquid gallon is exactly 3.785411784 liters, so you can trust the numbers for cooking, DIY projects, travel planning, and schoolwork.

How to use the unit converter

1Pick a category: Length, Weight, Temperature, or Volume.
2Enter the value you want to convert.
3Choose the unit you're converting from and the unit you want.
4Read the result and the exact conversion factor used, no guessing.

Good to know

All conversions run entirely in your browser with no page reloads and no data sent anywhere, so the tool works fast and keeps your inputs private. Switch tabs to jump between categories; your from and to units reset to the most common US-first pairing for each category, and the swap button flips the direction in one tap.

Frequently asked questions

The US liquid gallon (3.78541 liters) and its US quarts, pints, and fluid ounces, the units used on US recipes, fuel economy figures, and drink packaging.

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