Unit Converter
Convert between units of length, weight, temperature, and data storage. Switch tabs for each category, choose your units from dropdowns, and enter a value to see the instant conversion.
Standalone Converters
Need a dedicated page for one measurement type? Each converter below focuses on a single category with a full unit list, worked examples, and a shareable URL.
How It Works
Unit conversion works by converting the input value to a canonical base unit, then converting from that base unit to the target. This eliminates the need to store a conversion factor for every possible pair of units.
Length — base unit: meters
mm: 1 m = 1000 mm → factor 0.001
cm: 1 m = 100 cm → factor 0.01
m: base → factor 1
km: 1 m = 0.001 km → factor 1000
in: 1 inch = 0.0254 m → factor 0.0254
ft: 1 foot = 0.3048 m → factor 0.3048
yd: 1 yard = 0.9144 m → factor 0.9144
mi: 1 mile = 1609.344 m → factor 1609.344
Weight — base unit: kilograms
mg: factor 0.000001
g: factor 0.001
kg: base → factor 1
t (metric ton): factor 1000
oz: 1 oz = 0.028349523 kg
lb: 1 lb = 0.45359237 kg
st (stone): 1 stone = 6.35029318 kg
Temperature — these have offsets, not just scale factors:
°C to °F: F = C × 9/5 + 32
°F to °C: C = (F − 32) × 5/9
°C to K: K = C + 273.15
K to °C: C = K − 273.15
Data storage — base unit: bytes
B: factor 1
KB: factor 1,024
MB: factor 1,048,576
GB: factor 1,073,741,824
TB: factor 1,099,511,627,776
PB: factor 1,125,899,906,842,624
Note: The tool uses binary (base-2) prefixes where 1 KB = 1,024 bytes, as used by operating systems. Some contexts (storage manufacturers, network speeds) use decimal (1 KB = 1,000 bytes); the difference becomes significant at TB scale.
Worked example: Convert 5 feet 11 inches to centimeters.
5 ft 11 in = (5 × 12 + 11) = 71 inches
71 inches × 0.0254 m/inch = 1.8034 m = 180.34 cm
Worked example: Convert 98.6°F to Celsius.
C = (98.6 − 32) × 5/9 = 66.6 × 0.5556 = 37.0°C
Need a dedicated converter for a specific category? This hub covers length, weight, temperature, and data in tabs. For more unit types — including area, volume, speed, time, pressure, energy, angle, and frequency — use the standalone converters linked below the tool.
Frequently Asked Questions
Why is 1 KB not exactly 1,000 bytes?
Because computers use binary (base-2) arithmetic. 2^10 = 1,024, which is close to 1,000, so early computer engineers called it a "kilo." This binary kilobyte became embedded in operating systems. To eliminate confusion, the IEC introduced "kibibyte" (KiB) for 1,024 bytes, reserving "kilobyte" (KB) for exactly 1,000 bytes — though OS X, Linux, and Windows still use KB to mean 1,024.
How many centimeters are in an inch?
Exactly 2.54 cm. This is the internationally defined exact value since 1959. So 1 foot = 30.48 cm, and 1 yard = 91.44 cm.
What is absolute zero in Celsius and Fahrenheit?
Absolute zero is 0 Kelvin = −273.15°C = −459.67°F. It is the lowest theoretically possible temperature, where all molecular motion stops.
How do I convert stone and pounds to kilograms?
First convert stone to pounds: multiply stone by 14. Then add any remaining pounds. Finally convert total pounds to kilograms by multiplying by 0.453592. Example: 11 stone 5 lbs = (11 × 14 + 5) = 159 lbs × 0.453592 = 72.12 kg.
What is a metric ton vs a US ton?
A metric ton (tonne) = 1,000 kg = 2,204.6 lbs. A US short ton = 2,000 lbs = 907.2 kg. A British long ton = 2,240 lbs = 1,016 kg. This converter uses the metric ton (1,000 kg).