10 metres in feet
One metre is 1 ÷ 0.3048 = 3.280 84 feet, so 10 metres is 32.808 4 feet.
The reverse factor is exactly 0.3048, because the foot has been defined in terms of the metre since 1959.
Unit converter
Pick a category, enter a value and choose the unit you want. The conversion is instant, the factor is shown, and the same value appears in every unit of that category.
Result
Fill in the fields to see your result.
How it works
Almost every conversion is a single multiplication. Each unit is defined as a fixed multiple of an SI base unit, so converting means going to the base unit and back out again: metres for length, kilograms for mass, joules for energy. Doing it in two steps rather than storing a factor for every pair keeps the numbers exact and avoids the drift that comes from chaining rounded constants.
Most of the factors are exact by definition rather than measured. Since 1959 an international inch is exactly 25.4 millimetres and an avoirdupois pound is exactly 0.453 592 37 kilograms — agreed values, not approximations. Where a factor genuinely is approximate, such as the speed of sound used for mach, the assumption is stated.
Temperature is the exception. Its scales differ by an offset as well as a factor, so there is no single number to multiply by, and this calculator shows the formula instead. That is also why 0 °C is not 0 °F, while 0 metres really is 0 feet.
Formulas used
Converting through the base unit
result = value × factor(from) ÷ factor(to)
Each factor expresses one unit in terms of the SI base unit of its category.
Worked examples
1 GB in GiB
A gigabyte is 10⁹ bytes; a gibibyte is 2³⁰ = 1 073 741 824 bytes. So 1 GB is 0.931 GiB.
This is why a drive sold as 1 TB shows as roughly 931 GB in an operating system that reports binary units. Nothing is missing; the two are counting differently.
Assumptions and limits
- Conversion factors are the exact values fixed by international agreement where such a definition exists.
- Mach is calculated at 343 m/s, the speed of sound in dry air at 20 °C; it varies with temperature.
- A month is taken as 30.44 days and a year as 365.25 days when converting durations.
- Digital storage distinguishes decimal (kB, MB) from binary (KiB, MiB) units, following the IEC standard.
Frequently asked questions
How many pounds are in a kilogram?
One kilogram is 2.204 622 6 pounds, because a pound is defined as exactly 0.453 592 37 kilograms. The everyday approximation of 2.2 is about 0.2% low, which matters on a shipment and not on a shopping list.
Why does my hard drive show less space than advertised?
Manufacturers count in decimal units — a terabyte is 10¹² bytes. Many operating systems display binary units, where a tebibyte is 2⁴⁰ bytes, about 10% larger. A 1 TB drive therefore appears as roughly 0.91 TiB.
Is a US gallon the same as an imperial gallon?
No. A US gallon is 3.785 41 litres; an imperial gallon is 4.546 09 litres, about 20% larger. The same applies to pints and fluid ounces, which is a common source of error in recipes.
Why can I not convert length into weight?
Because they measure different physical quantities. Converting requires a shared base unit, and there is none between a metre and a kilogram. To go from a volume to a mass you need a density, which is a separate calculation.
Sources
- BIPM — The International System of Units (SI)
- International yard and pound agreement, 1959
Updated
Related calculators
Temperature Convert between Celsius, Fahrenheit, Kelvin and Rankine, with the formula, the substitution and a table of familiar reference points. Area Find the area and perimeter of nine common shapes, entering each dimension in whatever unit you have to hand. Volume Find the volume and capacity of eight solids, from a packing box to a cylindrical tank, in any unit you need.