MEASUREMENT & METHODS

Feet (ft): length unit guide

Understand feet (ft) for length. Check base-unit equivalents, examples, comparison tables and source conventions.

What is being measured?

Length describes distance or a linear dimension. Area and volume require squared or cubed length units, not the same linear multiplier.

Distances use international definitions. Light-years use a 365.25-day Julian year. The parsec follows the IAU angular definition and uses finite numerical precision.

Meaning of ft

Feet uses the symbol ft in this library and measures length. Under the stated reference convention, 1 ft = approximately 0.3048 m. This equivalence changes how a known value is written. It does not increase measurement accuracy or establish whether a measurement is appropriate to a real application.

Conversion method

Multiply the value by the source factor (0.3048), then divide by the target factor (1). The factor ratio expresses the same length measurement in the other unit.

Worked example

For a known value of 10 ft, the reference conversion gives 3.048 m. Converting that result back gives approximately 10 ft. This reverse check helps catch a reversed factor, but matching round-trip arithmetic alone does not independently verify a source definition.

Common reference values

Input (ft)Reference equivalent (m)
10.3048
51.524
103.048
257.62
5015.24
10030.48

Compare one ft with other units

Target unitEquivalent of 1 ftDefinition guide
Metres (m)0.3048Read definition
Kilometres (km)0.0003048Read definition
Centimetres (cm)30.48Read definition
Millimetres (mm)304.8Read definition
Inches (in)12Read definition
Yards (yd)0.333333333333Read definition
Miles (mi)0.000189393939394Read definition
nautical miles (nmi)0.000164578833693Read definition

Precision and common mistakes

  • Keep the source and target quantity consistent. A matching symbol is not enough to establish a compatible definition.
  • Record the original measurement precision. Showing twelve significant digits in a table does not make a rounded input more precise.
  • Check symbol capitalization, prefixes and any regional convention in the source. Use the displayed unit definition rather than a similarly named unit.
  • Factors involving repeating fractions or π use finite numerical precision. Round the final answer to the precision justified by your input.

Use a working converter

Source and verification scope

Examples and tables are computed from the versioned unit definitions used by the linked converters. The source access dates appear below. Computandum is independent of the cited organizations; a citation does not mean that a publisher endorses this page or an actual project.

Sources

Read the calculation and sourcing methodology →