Unit converter
Type the conversion as you would ask it, or choose the units yourself. The answer comes with the factor, the working and a table of equivalents.
Enter one measure and see the answer, factor and equivalents.
Choose what you need to convert
9 everyday categories
Every length unit
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How to convert units
Enter the measurement
Type a command such as 5 ft 8 in to cm, or enter a number in either value field.
Choose the units
Search 60 categories or browse seven groups. Then choose the source and destination units. The answer updates immediately.
Check and use the answer
Read the exact relationship and calculation rule. Copy the value or the complete equation when you are ready.
A converter that shows its work
A conversion result is only useful when you can tell which unit it means. This tool keeps the source, destination and relationship visible together. It also separates units that share a familiar name. A US gallon and an imperial gallon are different choices, for example.
Most categories use one reference unit. Length values convert through the metre, mass through the kilogram and pressure through the pascal. Temperature needs an offset as well as a scale. Fuel economy is reciprocal. The working line changes to match those cases instead of pretending every conversion is one multiplication.
Sixty categories, one consistent method
The category browser covers everyday measures, mechanics, heat, electricity, magnetism, light, radiation, data and chemistry. Length runs from nanometres to light-years. Electrical quantities include current, charge, potential, resistance, conductance, capacitance and inductance. Radiation units keep activity, absorbed dose, equivalent dose and exposure in separate categories because they measure different things.
| What you type | Answer | What it checks |
|---|---|---|
5 ft 8 in to cm | 172.72 cm | Adds both source measures before converting. |
72 F to C | 22.2222222222 °C | Uses the temperature offset and scale. |
1 gal to L | 3.785411784 L | Reads an unqualified gallon as US customary. |
60 mph to km/h | 96.56064 km/h | Uses the international mile of exactly 1.609344 km. |
What it deliberately does not guess
The parser only combines measures from one category. It can add feet and inches, but it will not interpret a compound engineering expression such as newton-metres per second. Calendar months are also excluded because they do not have a fixed length. The time category uses a Julian year of exactly 365.25 days and labels it.
Currency is absent because exchange rates change and require a live source. Clothing and shoe sizes are regional tables rather than units. Medicine is outside the tool's scope because a safe dose depends on more than units. These limits keep a precise converter from looking more capable than it is.
Frequently asked questions
Which units can I convert?
The converter covers 436 units in 60 categories. These include everyday measures, mechanics, heat, electricity, magnetism, light, radiation, data and chemistry. Search by a quantity such as pressure or by a unit such as lux, ohm or poise.
Can I type a conversion instead of choosing units?
Yes. Try 12.5 cm to in, 5 ft 8 in to cm or 72 F to C. It accepts decimals, ordinary fractions and mixed measures within one category. Spell out an ambiguous abbreviation if the tool asks you to.
Are US and imperial gallons the same?
No. One US gallon is 3.785411784 litres. One imperial gallon is 4.54609 litres. They appear as separate units, along with separate US and imperial cups, pints and fluid ounces where needed.
How many decimal places does the converter use?
Auto precision keeps up to 12 significant digits and removes empty trailing zeros. You can choose 3, 5, 8, 12 or 15 significant digits. The setting changes the displayed answer, not the conversion factor used in the calculation.
Why is fuel economy conversion different?
Miles per gallon measures distance per fuel. Litres per 100 kilometres measures fuel per distance. One rises while the other falls, so the relationship is reciprocal rather than a simple multiplication.
Can I use this for medicine or dosing?
No. It converts units, but it does not check substances, concentrations, patient details or clinical instructions. Use the dose and method supplied by a qualified clinician or pharmacist.
Does the converter upload what I type?
The calculation runs in your browser. Signed in, your text and settings save automatically to your private account. Signed out, they remain in this browser.
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