How this calculator works
The international foot is exactly 0.3048 m and the centimetre is 0.01 m, so one foot is 0.3048 / 0.01 = 30.48 cm exactly. Metric plans and furniture dimensions are usually given in centimetres, while imperial plans use feet and inches, so this page is useful when reading a drawing in the other system. Decimal feet multiply by 30.48 directly. A value such as 5.9 ft means 5.9 feet, which is 5 ft 10.8 in, not 5 ft 9 in.
Formula
centimetres = feet x 30.48. feet = centimetres / 30.48. 1 ft = 30.48 cm = 12 in exactly.
Worked example
6 ft is 6 x 30.48 = 182.88 cm. A 170 cm doorway is 170 / 30.48 = 5.57743 ft. 5 ft 7 in is 5.58333 ft, or 170.18 cm. A 2,000 mm shelf is 200 cm, or 6.56168 ft.
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Frequently asked questions
Is 30.48 exact or rounded?
It is exact. The international foot was defined as exactly 0.3048 m in 1959, and a centimetre is exactly 0.01 m, so 30.48 cm per foot involves no rounding.
How do I enter a height given in feet and inches?
Divide the inches by 12 and add them to the feet first. For 5 ft 7 in, 7 / 12 = 0.58333, so enter 5.58333 ft and the answer is 170.18 cm.
Which is bigger, a foot or 30 cm?
A foot is slightly bigger: 30.48 cm against 30 cm, a difference of 1.6 per cent. The gap adds up over a long measurement, so use the exact factor for plans rather than a rule of thumb.
Does this work for a person's height?
Yes. The same factor converts a stature in feet to centimetres. For a full height readout in feet and inches, the height converter is easier because it takes the two fields separately.