Unit Converter — Length, Weight, Temperature & More
Science lab asks for millilitres but you only know cups? Recipe in grams but your scale reads pounds? Pick your unit category, type your value, and get the answer instantly — no sign-up, no ads.
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The conversions below cover the ones that come up most often — whether you're working through a chemistry problem set, following a recipe from another country, or trying to make sense of a measurement from a textbook that uses a different system than you're used to. Keep this page open during labs or cooking and skip the Google detour. If you need a dedicated page for a specific conversion, try cm to inches (with a full height table), °F to °C (with Kelvin and reference points), pounds to kg (with a body weight table), or mL to cups (for lab and kitchen volumes). If you're converting grades between GPA systems instead of physical units, the CGPA converter handles that.
Quick Reference
📏 Length
1 inch2.54 cm
1 foot30.48 cm
1 yard0.9144 m
1 mile1.609 km
1 km0.621 miles
⚖️ Weight
1 kg2.205 lbs
1 lb453.6 g
1 oz28.35 g
1 stone6.35 kg
1 tonne1,000 kg
🌡️ Temperature
0°C (freezing)32°F
20°C (room)68°F
37°C (body)98.6°F
100°C (boiling)212°F
0 K (absolute zero)−273.15°C
🧪 Volume
1 litre0.264 US gal
1 US gallon3.785 L
1 US cup236.6 mL
1 tablespoon14.79 mL
1 teaspoon4.93 mL
Frequently Asked Questions
The formula is °C = (°F − 32) × 5/9. If you need a quick mental approximation without a calculator: subtract 32, then halve the result and add 10% back. Example: 68°F → subtract 32 = 36 → half = 18 → add 10% (1.8) → about 19.8°C (actual is 20°C). Works well enough for everyday use. Going the other way (°C to °F): multiply by 9/5, then add 32.
Add 273.15 to the Celsius value: K = °C + 273.15. Example: 25°C = 298.15 K, and 100°C (boiling) = 373.15 K. Kelvin is the SI base unit of temperature used in chemistry, physics, and thermodynamics — you'll encounter it constantly in lab reports and gas law equations. Absolute zero (0 K) = −273.15°C, the coldest theoretically possible temperature. Use the Temperature tab in the converter above to switch between °C, °F, and K instantly.
1 US cup = 236.6 mL. In lab settings, 250 mL is often used as a practical approximation since it's a standard beaker size. Other useful lab conversions: 1 tablespoon = 14.79 mL, 1 teaspoon = 4.93 mL, 1 fluid ounce = 29.57 mL. These come up constantly in chemistry labs and biology practicals where procedures use mL but your intuition is still in cups or teaspoons.
They're not the same — a US gallon is 3.785 litres, while a UK (Imperial) gallon is 4.546 litres, about 20% larger. This matters when you're following a recipe, comparing fuel efficiency, or buying beverages. UK and Australian recipes use Imperial gallons (and pints); US recipes and vehicles use US gallons. If a recipe or fuel figure doesn't specify, check the source country — mixing the two is a surprisingly common mistake.
A hectare is 10,000 square metres — picture a square with 100-metre sides. That's roughly the size of a standard soccer/football pitch. In practical terms: 1 hectare equals about 2.47 acres, and 100 hectares make up 1 square kilometre. You'll run into hectares in geography, environmental science, and agriculture — they're the metric world's answer to the Imperial acre.
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