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Universal Unit Converter
The ultimate free online tools for everyone. From Physics and Engineering to International Shopping and Home Living. Accurate, visual, and easy to use.
Science & Engineering
Core Tools
Physics & Math
High-precision converters for academic and professional use.
m
kg
K
Length
m, ft, in, ly
Weight
kg, lbs, oz
Temp
°C, °F, K
Volume
L, gal, ml
Area
m², acres
Speed
mph, km/h
Energy
J, cal, kWh
Pressure
Pa, bar, psi
Power
W, kW, hp
Storage
TB, GB, MB
Force
N, lbf
Torque
N·m, lb·ft
PDF & Documents
Digital Tools
Lifestyle & Personal
Finance
Health & Fitness
🔥 Trending Conversions
Measurement Guides & Insights
Learn the history, science, and practical applications behind every unit conversion.
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Tons vs Kilonewtons: The Dangerous 'Ton' Trap in Engineering
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Why Meteorologists Don't Use PSI: Understanding hPa & Barometers
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Metric vs Imperial Memes
Because unit conversion doesn't have to be boring!
When Americans Visit Europe
Celsius vs Fahrenheit wars never end
"Europeans: It’s only 40°C, just a bit warm. Americans: Bro, that’s 104. I’m MELTING ☠️"
Cooking Recipe Conversions
Every baker’s struggle with grams vs cups
"Chef: Add 200 grams of flour. Me: Okay, but how many coffee mugs is that? 🫠"
Science Class Flashbacks
That dreadful SI unit moment
"Teacher: Show all unit conversions. Me: Shows vibes 😎"
Gym Weight Confusion
Traveling between lbs and kgs feels illegal
"Me in the US: Benches 100 lbs 🇺🇸 Me in Europe: Benches 45 kg 🇪🇺 Also me: Wow, I got weaker crossing the ocean 💀"
Gas Station Math
Fuel efficiency makes no sense across borders
"American: 30 MPG is amazing! 🚗 European: 7 L/100km is amazing! ⛽ Me: Both are numbers. I walk now 🚶♂️"
International Engineering
Why unit conversions matter in real life
"NASA: We lost a $125M Mars orbiter 😭 Reason: Inches vs Centimeters. Earth: Bro rage quit over math 🤦♂️"
The Fahrenheit Flex
When Celsius people hear Americans talk weather
"American: It's 100 degrees today 🔥 European: BRO, you'd be vapor by now ☠️"
Metric vs Imperial Rulers
The eternal battle in school geometry
"Teacher: Draw a 10 cm line. Me: Whips out a 12-inch ruler. Brain: Divide by 2.54 real quick 😵"
Weighing Produce Abroad
Buying bananas should not require math
"Cashier: 2 kilos of apples please 🍎 Me: Uh… so that’s like… 4 footballs worth? 🏈"
Did You Know?
The metric system is used by 95% of the world's population, making it the global standard for science and trade.
One inch equals exactly 2.54 centimeters. This definition was internationally agreed upon in 1959.
The Kelvin scale starts at absolute zero (-273.15°C), where all atomic thermal motion ceases.
A liter was originally defined as the volume of 1 kg of water at 4°C (maximum density).
One horsepower (745.7 watts) was coined by James Watt to compare steam engines to draft horses.
Standard atmospheric pressure (1 atm) is defined as 101.325 kPa at sea level.