How do I convert Foot (ft) to Inch (in)?

1 ft equals 12 in using SI-based conversion and precise factors.

What is the formula to convert Foot (ft) to Inch (in)?

This is a linear unit conversion using a constant factor between units.

How can I share a direct ft to in result?

Use the shareable URL: https://measurecalc.com/convert/foot-to-inch

Convert Foot (ft) to Inch (in)

Q: Is Foot (ft) to Inch (in) conversion exact?

The result uses the defined conversion factors for these units; displayed values may be rounded.

Category: Length

Value From To Precision

12 in

1 ft = 12 in

Precision: 6 decimals; very small non-zero results use significant digits.

How to convert foot (ft) to inch (in)

Length measures distance or size. In SI it derives from the meter, defined via the speed of light, which ensures exact, reproducible conversions. Typical applications include construction, mapping, manufacturing tolerances, and navigation; legacy units like inches and feet remain common in trade and building plans.

Share this conversion: /convert/foot-to-inch

Quick conversion table

Handy values for Foot (ft) to Inch (in). Click a value to calculate that result.

Foot (ft)	Inch (in)
	12
	6
	30
	120

Conversion formula

Use the following formula:

Inch (in) ≈ Foot (ft) × 12

Convert length from Foot (ft) to Inch (in) using a fixed unit ratio. Round only the final result.

Common mistakes

Confusing international foot (0.3048 m) with legacy ‘US survey foot’ in old datasets.
Rounding mid-calculation; keep precision to the end.

Unit facts

Foot (ft): The foot is exactly 0.3048 meters (1959). Common in construction, aviation (runway lengths), and everyday use in US/UK.
Inch (in): The inch is exactly 25.4 millimeters (since 1959). Historically based on a thumb’s width; standardized for engineering and trade.

About Foot (ft)

Foot (ft)

Equals 12 inches; exactly 0.3048 m. Common for human height, room dimensions, and altitude in aviation (with feet for flight levels).

History: Standardized as the ‘international foot’ in 1959; the legacy US survey foot persisted for geodesy until its retirement in 2023 in favor of the international definition.

About Inch (in)

Inch (in)

Imperial/US unit exactly defined as 25.4 mm. Still widespread in hardware, displays (screen size), and woodworking. Conversions to/from SI are exact thanks to the 1959 agreement.

History: Various historic definitions existed; international inch was fixed at exactly 25.4 mm in 1959 by US, UK and Commonwealth countries to harmonize trade.

Frequently asked questions

How many Inch (in) are in one Foot (ft)?

1 Foot (ft) equals 12 Inch (in).

Is Foot (ft) to Inch (in) conversion exact?

Many unit conversions are exact by definition, while others use standardized conversion constants.

What is the fastest way to convert Foot (ft) to Inch (in)?

Enter a value in Foot (ft), choose Inch (in) as the target unit, and the calculator will instantly return the result.

Convert Foot (ft) to other units

ft → m Meter (m)

Convert other units to Inch (in)

cm → in Centimeter (cm)
m → in Meter (m)
mm → in Millimeter (mm)