Feet to mm Converter
Convert feet and millimeters in either direction using the exact international-foot definition.
Feet to millimeters formula
Millimeters = feet × 304.8. The factor is exact: 1 ft = 304.8 mm. For example, 3.5 feet × 304.8 = 1,066.8 millimeters.
Common feet to mm values
| Feet | Millimeters |
|---|---|
| 0.5 ft | 152.4 mm |
| 1 ft | 304.8 mm |
| 3 ft | 914.4 mm |
| 3.5 ft | 1,066.8 mm |
| 10 ft | 3,048 mm |
| 100 ft | 30,480 mm |
Millimeters to feet
Feet = millimeters ÷ 304.8, or millimeters × 1/304.8. A length of 304.8 mm equals exactly 1 ft. A length of 1,000 mm displays as approximately 3.28084 ft because the decimal continues beyond six places.
Paste a labeled value or swap direction
A written unit sets the direction automatically. You can paste “3.5 feet” while Millimeters is selected, or paste “1000 mm” while Feet is selected. Swap carries the unrounded valid result into the other direction. Enter only one unit at a time; mixed feet-and-inches notation is not interpreted.
Why 304.8 is exact
The international foot is defined as exactly 0.3048 meters. Since one meter equals 1,000 millimeters, one foot equals exactly 304.8 millimeters. Display rounding changes only the visible decimal, not the factor used by the calculator.
Frequently asked questions
How many millimeters are in one foot?
One international foot equals exactly 304.8 millimeters. Multiply feet by 304.8 to convert.
How do I convert millimeters to feet?
Divide millimeters by 304.8. For example, 304.8 mm equals 1 ft, while 1,000 mm displays as approximately 3.28084 ft.
Can I paste ft, foot, feet, or mm?
Yes. The converter recognizes ft, foot, feet, mm, millimeter, millimeters, millimetre, and millimetres. A pasted unit overrides the selected direction.
Why does the result sometimes show ≈?
The calculator uses the exact 304.8 factor internally and displays up to six decimal places. The ≈ symbol appears only when the displayed result is rounded.
Can I enter feet and inches together?
No. Enter one length in feet or millimeters. Mixed feet-and-inches notation needs a separate conversion step and is rejected here rather than guessed.