Unit Converter

Unit Converter online

Convert between millimetres, centimetres, metres, kilometres, inches, feet, yards and miles, using the exact international factors listed below — the same definitions surveyors and engineers work to.

How it works

Every conversion runs through metres: Result = Value × Factor[From] ÷ Factor[To], using mm: 0.001, cm: 0.01, m: 1, km: 1000, in: 0.0254, ft: 0.3048, yd: 0.9144, and mi: 1609.344. The answer is printed with the target abbreviation, such as 3.28084… ft. The form opens with 1 converting from Meter to Foot, so your first click already demonstrates the headline metric–imperial bridge.

Worked example

Converting 1 m to ft: 1 × 1 ÷ 0.3048 = 3.28084 ft (approximately). Reversing it, 10 ft to m: 10 × 0.3048 ÷ 1 = 3.048 m exactly. A site distance of 5 km to ft: 5 × 1000 ÷ 0.3048 = 5000 ÷ 0.3048 ≈ 16404.2 ft. And within imperial, 6 ft to in: 6 × 0.3048 ÷ 0.0254 = 72 in, confirming the familiar 12-inches-per-foot rule the factors encode. And a road distance of 1 mi to km: 1 × 1609.344 ÷ 1000 = 1.60934 km.

Units

Eight length units are supported — Millimeter (mm), Centimeter (cm), Meter (m), Kilometer (km), Inch (in), Foot (ft), Yard (yd), and Mile (mi) — with these exact relationships:

• 1 km = 1000 m
• 1 m = 100 cm = 1000 mm
• 1 mi = 1609.344 m = 1.609344 km
• 1 yd = 3 ft = 0.9144 m
• 1 m ≈ 3.28084 ft
• 1 ft = 12 in = 0.3048 m
• 1 in = 0.0254 m (2.54 cm)

Practical tips

• Convert slab depths carefully. A 6-inch slab is 6 × 0.0254 = 0.1524 m — entering 6 as metres would oversize the pour nearly forty-fold.
• Keep kilometres for site distances. Access roads and chainages stay readable in km; switch to m or ft only for member sizes.
• Round for cutting, not for records. The raw quotient carries full floating-point precision, so trim displayed decimals to what your tape measure can actually mark.
• Re-check the direction. Converting 1 ft → m gives 0.3048 while 1 m → ft gives 3.28084; a swapped From/To pair is the most common wrong answer.

Edge cases and limitations

• Six significant figures. Results are printed with up to 6 significant digits, which is more than a tape measure can justify but not survey-grade: a 100 km baseline converts to 62.1371 mi, and the hidden remainder matters over engineering distances.
• The factors are exact, not measured. Since 1959 the inch has been defined as exactly 25.4 mm, which fixes the foot at 0.3048 m, the yard at 0.9144 m and the mile at 1,609.344 m. Conversions here never accumulate rounding error from the factors themselves.
• Length only — areas do not scale linearly. There are no area or volume units on this page. To convert square metres to square feet, multiply by 10.7639 (the length factor 3.28084, squared); for cubic units, cube it (× 35.3147).
• Negative values convert symmetrically. Useful for levels below a datum or depths: −5 ft converts to −1.524 m with the same factor.

Privacy and browser processing

Conversions run locally in your browser — the values you enter never leave your device.

Frequently asked questions

Which units does this converter support?

Eight length units: Millimeter (mm), Centimeter (cm), Meter (m), Kilometer (km), Inch (in), Foot (ft), Yard (yd), and Mile (mi). This page covers length only — there are no weight or temperature options.

How many feet are in one metre?

About 3.28084 ft. The tool divides by the exact factor 0.3048 m per foot, so 1 ÷ 0.3048 = 3.28084…

How do I convert kilometres to feet for a site distance?

Enter the value with From set to Kilometer and To set to Foot. For example, 5 km gives 5000 ÷ 0.3048 ≈ 16404.2 ft.

Can I convert feet to inches here?

Yes. Select From Foot and To Inch — 6 ft converts as 6 × 0.3048 ÷ 0.0254 = 72 in, matching 12 inches per foot.

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