Reference formulas and worked examples below keep their stated units. Monetary examples use USD; dimensional examples use US customary units unless labeled otherwise. Metric calculator inputs are converted to these reference units before calculation. Choosing another currency does not convert example amounts or exchange money.
How to use this unit converter
Units are selected within this tool. The site’s regional preferences do not override your choices. For temperature, choose an absolute reading or a temperature difference.
How the calculation works
For ordinary linear conversions, result = input × source factor ÷ target factor. Each quantity family has its own base unit, so incompatible quantities cannot be mixed.
Absolute temperature conversion includes offsets: K = °C + 273.15 and °F = °C × 9/5 + 32. Absolute readings below zero kelvin are rejected. Temperature differences omit the offsets: a change of 10 °C is a change of 18 °F.
US liquid gallons, Imperial gallons, US customary cups and 250 mL metric cups are separate units. Duration days are exactly 24 hours and weeks exactly 7 days; calendar months, calendar years and currency exchange are not included.
Worked example
1 meter equals approximately 3.28083989501 feet. One US liquid gallon is 3.785411784 liters, while one Imperial gallon is 4.54609 liters. An absolute reading of 0 °C equals 32 °F; a difference of 0 °C equals a difference of 0 °F.
Limits and assumptions
Standard scalar conversions only. A unit change does not convert unrelated quantities such as mass to volume without density, or energy to power without time. Absolute temperature is bounded by zero kelvin. No live currency rates, calendar-month lengths, historical local units, pressure gauge offsets or uncertainty propagation.
Frequently asked questions
Does a gallon always mean the same volume?
No. Select US liquid gallon or Imperial gallon explicitly. Their liter values differ. The same care applies to fluid ounces and cups.
Why is a temperature difference converted differently?
A difference uses only the ratio of degree sizes. An absolute temperature also needs the zero-point offset between scales.
Can I swap source and target?
Yes. Swap units uses the current unrounded result as the new input and exchanges the two units, preserving the quantity. Invalid inputs must be corrected first.
Can I use scientific notation?
Yes, for example 1.25e3 means 1,250. The interface also accepts valid comma grouping, such as 1,250.
Can I convert pounds to liters?
Not directly. Pounds measure mass and liters measure volume; you also need the material’s density. This converter keeps those quantity families separate.