Feet to Millimeters Converter
Convert Feet (ft) to Millimeters (mm) instantly, or use the conversion table below to look up common values.
Feet to Millimeters conversion table
| Feet (ft) | Millimeters (mm) |
|---|---|
| 1 | 304.8 |
| 2 | 609.6 |
| 3 | 914.4 |
| 4 | 1,219.2 |
| 5 | 1,524 |
| 10 | 3,048 |
| 25 | 7,620 |
| 50 | 15,240 |
| 100 | 30,480 |
How to convert Feet to Millimeters
1 ft equals 304.8 mm. Use the converter above for any value, or read the table for common conversions.
mm = ft × 304.8 · ft = mm × 0.0032808398950131233Multiply a feet figure by 304.8 to get millimeters, or divide it by 0.003281 to go the other way.
Worked examples
- 1 ft= 304.8 mm
- 5 ft= 1,524 mm
- 10 ft= 3,048 mm
- 25 ft= 7,620 mm
- 100 ft= 30,480 mm
What these units are
Feet (ft). A foot is exactly 0.3048 meters, or 12 inches. It is used for height, altitude in aviation and room dimensions wherever imperial measurements are standard.
Millimeters (mm). A millimeter is one thousandth of a meter. It is the unit for precision work — engineering tolerances, rainfall, wire gauges and the thickness of paper or sheet metal.
Metric-to-metric conversions are exact. Imperial figures are exact by definition but are rounded for display, so a value converted back and forth can differ in the final digit.
Converting Feet to Millimeters in practice
Working in feet
The foot is exactly 0.3048 meters, or twelve inches. United States survey work has used a separate survey foot, defined as 1200/3937 meters and equal to about 0.3048006 meters.
Aviation uses feet for altitude and flight levels worldwide, even in countries that measure road distance in kilometers. Building heights, room dimensions, timber and, in some places, body height are also quoted in feet.
The metric conversion is exact, since the foot is defined as 0.3048 meters, and the reverse is exact too. A displayed result is rounded to six decimal places at most, so a round trip can differ in the final digit.
The common slip is assuming a foot is close to a third of a meter when it is slightly longer, so rough mental division undershoots. Feet also belong to length, while square feet measure area and cubic feet measure volume.
The foot competes with the meter for height and building dimensions and with the inch for small spans. Because one meter is a little over three feet, treating a meter figure as feet overstates a dimension more than threefold.
Checking a feet to millimeters conversion
Inside the metric units every length conversion is a shift of the decimal point, so millimeters to centimeters, meters to kilometers and the rest can be done by moving it. Which way, and how far, follows from the prefix alone.
Converting between metric and imperial is not a shift but a single exact multiplication, and the factor is the same one for that pair however large or small the value. The trap is mixing the two systems halfway, as when a distance is stated in meters and inches in the same sentence.
To check a length conversion, run it backwards, or convert through a familiar middle value such as a meter or a foot. The one thing to keep straight is pairs that differ by a thousand rather than by ten, since those are where a misplaced decimal point survives unnoticed.
Tanzania reference points
Real quantities, converted into the units on this page.
Uhuru Peak on Mount Kilimanjaro, the highest point in Africa
5,895 m = 19,340.551181 ft = 5,895,000 mm
The datasheet also records Kilimanjaro as rising 4,877 m above the surrounding plains.
Source: UNEP-WCMC World Heritage datasheet — Kilimanjaro National Park · verified 2026-09-14
Marangu Gate, the main road entrance to Kilimanjaro National Park
1,830 m = 6,003.937008 ft = 1,830,000 mm
Source: UNEP-WCMC World Heritage datasheet — Kilimanjaro National Park · verified 2026-09-14
How far Mount Kilimanjaro rises above the plains around it
4,877 m = 16,000.656168 ft = 4,877,000 mm
Source: UNEP-WCMC World Heritage datasheet — Kilimanjaro National Park · verified 2026-09-14
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