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Unit converter

Four categories, kept separate so the tool never offers to convert kilograms into miles.

The factors are the exact definitions rather than rounded measurements.

What are you converting
0.393701

1 cm is 0.393701 in

The factors here are the exact definitions rather than rounded measurements. An inch is exactly 25.4 mm and a pound is exactly 0.45359237 kg by international agreement. Answers are capped at six significant figures, because a converter that prints 2.5400000000000005 has told you the truth about floating point and nothing about the measurement.

Questions

Is anything I type sent anywhere?
No. Every calculator here runs in the page itself. There is no server that receives your date of birth, your loan or anything else, and you can check it in your browser's network tab: using a tool produces no request carrying what you typed.
Why is temperature handled differently?
Because it is not a ratio. Celsius, Fahrenheit and Kelvin start in different places, so 20 degrees is not twice 10 in any of them. Converting temperature by multiplying is the single most common bug in a converter, and it gets a separate path here.
How exact are the factors?
Exact. An inch is defined as 25.4 mm and a pound as 0.45359237 kg by international agreement, so those digits are definitions rather than measurements. Answers are capped at six significant figures, because printing 2.5400000000000005 says something true about floating point and nothing about your measurement.
Why are marla and kanal in the area list?
Because property in Pakistan and northern India is measured in them and most converters leave them out. The values used are the standard ones: a marla is about 25.29 square metres and a kanal is twenty marla. Regional variants exist, so check against a local deed if it matters.

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