Feet to Millimeters Converter
Enter the length in feet below to convert it to millimeters.
Convert Feet to Millimeters
Enter a value in feet (ft) to convert to millimeters (mm).
Feet to Millimeters Conversion Chart (1–40 Continuous)
Continuous 1 to 40 feet lookup table with exact decimals and reduced nearest 1/64 fractions. Highlighted rows mark common shop and ruler values.
| Feet (ft) | Decimal (mm) | Fraction — Nearest 1/64 (Reduced) | Nearest 1/16 (Tape) |
|---|---|---|---|
1 ft★ Common | 304.8 mm | 304 51/64 mm | 304 13/16 mm |
2 ft★ Common | 609.6 mm | 609 19/32 mm | 609 5/8 mm |
3 ft★ Common | 914.4 mm | 914 13/32 mm | 914 3/8 mm |
4 ft | 1,219.2 mm | 1219 13/64 mm | 1219 3/16 mm |
5 ft★ Common | 1,524 mm | 1524 mm | 1524 mm |
6 ft★ Common | 1,828.8 mm | 1828 51/64 mm | 1828 13/16 mm |
7 ft | 2,133.6 mm | 2133 19/32 mm | 2133 5/8 mm |
8 ft★ Common | 2,438.4 mm | 2438 13/32 mm | 2438 3/8 mm |
9 ft | 2,743.2 mm | 2743 13/64 mm | 2743 3/16 mm |
10 ft★ Common | 3,048 mm | 3048 mm | 3048 mm |
11 ft | 3,352.8 mm | 3352 51/64 mm | 3352 13/16 mm |
12 ft★ Common | 3,657.6 mm | 3657 19/32 mm | 3657 5/8 mm |
How to Convert Feet to Millimeters
To convert feet to millimeters, multiply the length by the following conversion ratio: 304.8 millimeters/foot.
Since one foot is equal to 304.8 millimeters, you can use this simple formula to convert:
The length in millimeters is equal to the length in feet multiplied by 304.8.
For example, here's how to convert 5 feet to millimeters using the formula above.
How Many Millimeters Are in a Foot?
There are 304.8 millimeters in a foot, which is why we use this value in the formula above.
Our foot fraction and decimal calculator can convert feet and millimeters, and it automatically converts the results to US customary, imperial, and SI metric values.
Feet and millimeters are both units used to measure length. Keep reading to learn more about each unit.
How to Convert Feet to Fractional Inches (1/16″, 1/32″ & 1/64″)
Plain-language method for turning decimal inches into a standard tape-measure or machinist ruler fraction
Calculators give you a decimal number (such as 60 in), but tape measures and woodworking rulers are marked in binary fractions of an inch—most commonly 1/16″ on carpenter tapes, 1/32″ on fine woodworking rules, and 1/64″ on machinist scales.
Here is the step-by-step worked example for converting 5 feet (ft) into fractional inches:
- Find the decimal inches result: Convert 5 ft to inches to get 60 in.
- Separate the whole inches from the decimal part: Keep the whole number 60 aside, leaving the decimal remainder 0.
- Multiply the decimal part by your desired fraction denominator (16, 32, or 64) and round half up: Multiply 0 by 16, 32, or 64, then round to the nearest whole number (values ending in .5 round up).
- Reduce the fraction to lowest terms: If the rounded top number (numerator) is even, divide both top and bottom by 2 (or their Greatest Common Divisor) until the top number is odd, then combine with your whole inches.
What Is a Foot?
A foot is a US customary and imperial unit of length equal to 12 inches or 1/3 of a yard. Under the 1959 International Yard and Pound Agreement, one foot is legally defined as exactly 0.3048 meters (30.48 centimeters). [1]
Feet are widely used in the United States, Canada, and the United Kingdom for human height, building construction, real estate floor plans, and aviation altitude. Feet can be abbreviated as ft; for example, 1 foot can be written as 1 ft.
Feet can also be denoted using the ′ symbol, known as a prime (or a single quote ' for convenience). For example, 5 feet 10 inches is frequently written as 5′ 10″ or 5' 10".
Feet are measured using 12-inch rulers, carpenter's folding rules, 25-foot steel tape measures, and laser distance meters across residential framing, architecture, and surveying.
What Is a Millimeter?
A millimeter is a metric unit of length equal to one-thousandth (1/1,000) of a meter or one-tenth (1/10) of a centimeter. By international definition, there are exactly 25.4 millimeters in one inch. [2]
The millimeter, or millimetre, is a standard SI metric unit of length. Millimeters can be abbreviated as mm; for example, 1 millimeter can be written as 1 mm.
In the metric system, "milli" is the prefix for thousandths, or 10⁻³. Millimeters are the default unit on mechanical engineering drawings and architectural blueprints worldwide.
Millimeters are commonly measured using metric steel rules, digital vernier calipers, depth gauges, and micrometers in CNC machining, 3D printing, automotive fasteners, and precision manufacturing.
When converting length between feet (ft) and millimeters (mm), keep full floating-point precision (1' = 304.8 mm; 1 mm = 0.0032808 ft) during intermediate calculations and round only the final millimeter figure to match your instrument tolerance.
More Foot & Millimeter Conversions
Need to calculate in the opposite direction? Use our millimeters to feet calculator to switch your starting unit immediately. You can also explore related tools such as converting millimeters to feet, converting inches to millimeters, or converting micrometers to millimeters.
Frequently Asked Questions
References
- [1]NIST OWM StandardNIST OWM (SI Units — Length)·Length Metrology Standard — Feet (ft) to Millimeters (mm)
- [2]BIPM SpecificationBIPM (SI Base Unit: Metre (m))·Unit Specifications: Foot (ft) & Millimeter (mm)
- [3]NIST HB 133 ReferenceNIST HB 133 (NIST Handbook 133 (2019 Ed.))·Conversion Factors & Mathematical Basis (ft to mm)