Unit Converter

What is a unit converter?

A unit converter is a tool that converts length, weight, temperature, and volume between common metric and imperial units. Enter a value and units — this page is not a universal converter for every measurement type.

How to Use the Unit Converter

1. Select a category. Choose the type of measurement: length, weight, temperature, or volume.
2. Enter your value. Type the number you want to convert.
3. Select your units. Choose your starting unit (for example, Celsius) and your target unit (for example, Fahrenheit).
4. Read your result. The converted value appears instantly using official conversion constants. Tiny floating-point display rounding can still appear on very small fractions.

Who Is This For?

• Students doing homework who need to convert between metric and imperial units for physics, chemistry, or math problems.
• Cooks converting recipe measurements from a foreign cookbook — grams to cups, Celsius to Fahrenheit, milliliters to fluid ounces.
• Anyone comparing product specs listed in unfamiliar units — screen sizes in inches vs. centimeters, engine displacement in liters vs. cubic inches, or clothing sizes listed in different measurement systems.

Key Benefits

• Privacy. Tool inputs stay in the browser.
• Free to use now — no account, no paywall. Ads are not live yet.
• No account required — open the page and start converting immediately.
• Official constants — uses official fundamental constants (the inch is defined as exactly 25.4 mm), not rounded textbook shortcuts. Tiny floating-point display rounding can still appear.

Common Unit Conversion Mistakes

• Confusing fluid ounces with ounces by weight — a fluid ounce measures volume; an ounce measures mass; they are different units with different conversion factors depending on the substance being measured.
• Using the wrong temperature formula — Celsius to Fahrenheit requires multiplying by 9/5 and adding 32, not simply multiplying by 2; the simple doubling shortcut produces results that are off by several degrees.
• Assuming metric prefixes are linear when they're exponential — 1 kilometer is 1,000 meters, but 1 kilogram is 1,000 grams; mixing up prefix scales (milli-, centi-, kilo-) is the most common source of unit conversion errors in science homework.

For cooking-specific volume and weight conversions, use our dedicated Kitchen Unit Converter which accounts for ingredient density. For area calculations, the Square Footage Calculator handles room measurements in both metric and imperial.

For the official SI unit definitions and conversion factors used in this tool, see the NIST Unit Conversion reference from the National Institute of Standards and Technology.

Common Use Cases

A student in Canada needs to convert their weight from kilograms to pounds for a US sports registration form. A home cook finds a British recipe specifying 250ml of cream and needs to know how many cups that is. A traveler packing for a trip to Europe checks that 20°C means a comfortable 68°F — light jacket weather, not winter coat weather. An online shopper compares a product's 15-inch measurement to their space measured in centimeters.

Frequently Asked Questions