Convert Foot to Inch
Convert feet to inches instantly. 1 foot = 12 inch — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Inch to Foot converter for the reverse conversion.
Units explained
Foot
A foot is an Imperial and US customary unit of length equal to 12 inches or exactly 0.3048 meters. It is the most commonly used unit of length in everyday measurement in the United States.
The foot's origin is literally the length of a human foot, used as a measurement standard since antiquity. The English foot was standardized at various points in history; the modern international foot (0.3048 m exactly) was fixed by the 1959 International Yard and Pound Agreement.
Feet are used in the US for body height, building dimensions, room sizes, road sign clearances, aviation altitude (feet above sea level), and most everyday distance estimation. The UK uses feet informally for height despite officially being metric.
Used since antiquity; standardized to 0.3048 m exactly by the International Yard and Pound Agreement of 1959. Aviation worldwide uses feet for altitude despite metric adoption elsewhere.
Inch
An inch is an Imperial and US customary unit of length defined since 1959 as exactly 25.4 millimeters (0.0254 meters). It is still the standard small unit of length in the United States, the United Kingdom (informally), and a few other countries.
The inch derives from the Roman uncia (one-twelfth of a foot) and survived through Anglo-Saxon and medieval English measurement systems. Various definitions persisted regionally until the 1959 International Yard and Pound Agreement standardized the inch globally as exactly 25.4 mm.
Inches are used in the US and UK for body height, screen sizes (TVs, monitors, phones), tire sizes, plumbing, lumber, paper sizes (US Letter is 8.5 × 11 in), and most consumer product specifications in the United States.
Anglo-Saxon origin (predating 1066); standardized to 25.4 mm exactly by the International Yard and Pound Agreement of 1959, signed by the US, UK, Canada, Australia, New Zealand, and South Africa.
Foot to Inch conversion formula
The relationship between feet and inches:
To convert feet to inches, multiply the value in feet by 12. To reverse, multiply inches by 0.0833333333.
How to use this converter
Type a value into the calculator. The result in inches updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Inch to Foot converter for the reverse direction.
Step-by-step: convert feet to inches
- Write down the value in feet (ft).
- Multiply that value by the factor 12.
- The product is the equivalent value in inches (in).
- To reverse, multiply the inch value by 0.0833333333.
Worked examples
Example 1 — Convert 1 ft to in:
1 × 12 = 12 in
Example 2 — Convert 100 ft to in:
100 × 12 = 1200 in
Real-world example — Standard ceiling height
An 8-foot ceiling height equals 96 inches — useful for hanging fixtures, where electricians measure cable drops in inches but the architect's drawing notes the room height in feet.
8 ft × 12 = 96 in
Real-world example — Hand width and grip measurements
A 4-foot length equals 48 inches. Construction crews ordering custom doors and trim convert feet to inches because suppliers ask for exact inch measurements but the rough framing is dimensioned in feet.
4 ft × 12 = 48 in
Real-world example — Adult height in feet to inches
A 6-foot-tall person measures exactly 72 inches. American driver's licences and medical records store height in feet-and-inches; converting feet to inches is the everyday arithmetic of those records.
6 ft × 12 = 72 in
Foot to Inch conversion table
Standard reference values for converting feet to inches:
| Foot [ft] | Inch [in] |
|---|---|
| 0.01 | 0.12 |
| 0.1 | 1.2 |
| 1 | 12 |
| 2 | 24 |
| 3 | 36 |
| 4 | 48 |
| 5 | 60 |
| 10 | 120 |
| 20 | 240 |
| 30 | 360 |
| 40 | 480 |
| 50 | 600 |
| 100 | 1200 |
| 500 | 6000 |
| 1000 | 12000 |
Frequently asked questions
How many inches is 1 foot?
How do I convert feet to inches?
How do I convert inches back to feet?
How many inches is 100 feet?
Popular length unit conversions
Convert Foot to other length units
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Metric / SI (18 units)
Imperial / US Customary (26 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 ft = 12 in) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.