Feet to Inches Converter
Convert feet to inches — twelve to the foot, the conversion behind every height and timber length. Results update as you type; exact factors shown.
One foot is 12 inchs — see the exact factor, not a rounded rule of thumb.
How the feet to inches converter works
Every length is converted through the meter, the SI base unit of length. The inch has been defined as exactly 25.4 mm since the 1959 international yard and pound agreement, so a foot is exactly 0.3048 m, a yard 0.9144 m and a statute mile 1,609.344 m. The nautical mile is 1,852 m by international definition.
The US uses customary units (US gallon, short ton, °F) in daily life; NIST SP 811 gives the exact SI factors.
Common length conversions
| From | To | Units |
|---|---|---|
| 1 ft | 12 in | foot to inchs |
| 2 ft | 24 in | feet to inchs |
| 3 ft | 36 in | feet to inchs |
| 4 ft | 48 in | feet to inchs |
| 5 ft | 60 in | feet to inchs |
| 5.5 ft | 66 in | feet to inchs |
| 6 ft | 72 in | feet to inchs |
| 6.5 ft | 78 in | feet to inchs |
| 8 ft | 96 in | feet to inchs |
| 10 ft | 120 in | feet to inchs |
| 12 ft | 144 in | feet to inchs |
| 20 ft | 240 in | feet to inchs |
Units in this converter and their exact factors
| Unit | Symbol | One unit in meters |
|---|---|---|
| millimeter | mm | 0.001 meter |
| centimeter | cm | 0.01 meter |
| meter | m | 1 meter |
| kilometer | km | 1,000 meter |
| inch | in | 0.0254 meter |
| foot | ft | 0.3048 meter |
| yard | yd | 0.9144 meter |
| mile | mi | 1,609.344 meter |
| nautical mile | nmi | 1,852 meter |
FAQFrequently asked questions about length conversion
How many inches in a foot?
Twelve, exactly.
How many inches is 5 foot 10?
70 inches — 5 × 12 plus 10.
How do I write a height in inches?
Multiply the feet by 12 and add the leftover inches.
How many inches in a yard?
36, because a yard is three feet.
Why twelve?
Twelve divides evenly by 2, 3, 4 and 6, which made halves, thirds and quarters easy long before decimals.
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Institute of Standards and Technology (NIST) — United States's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.