Divide by 100, or shift the decimal two places
metres = centimetres ÷ 100, centimetres = metres × 100
This ratio is exact: 1 m = 100 cm, no approximation. Because the metric system is decimal, the whole conversion is just a decimal shift. Moving the point two places left turns centimetres into metres (150 → 1.50 m); moving it two places right reverses it (2.5 m → 250 cm).
Common values
| Centimetres | Metres | Everyday sense |
|---|---|---|
| 10 cm | 0.1 m | Width of a hand |
| 30 cm | 0.3 m | A standard ruler |
| 100 cm | 1 m | Doorway height off the ground |
| 150 cm | 1.5 m | A shorter adult |
| 170 cm | 1.7 m | Average adult height |
| 200 cm | 2 m | A very tall person |
| 500 cm | 5 m | A parking space |
The same left-shift works for other metric steps: 1 cm = 10 mm, and 100,000 cm = 1 km.
Where the two units fit
- Centimetres for objects and bodies. Heights, clothing, furniture and wounds are recorded in cm because whole numbers read more cleanly than metre decimals.
- Metres for rooms and distances. Blueprints, land and larger spaces work in metres, with centimetres only for the fine detail.
- Not the same as millimetres. A centimetre is 10 mm. Precision work (engineering, machining) drops to mm; general measuring stays in cm.
Common questions
How many centimetres are in a metre?
Exactly 100. The prefix centi means one hundredth, so a centimetre is one hundredth of a metre. There is no rounding in this ratio.
How do I convert 150 cm to metres?
Divide by 100, which gives 1.5 metres. The shortcut is to move the decimal point two places to the left: 150 becomes 1.50.
Why do doctors record height in centimetres?
It is a habit of readability. On a form, 170 cm is clearer to write and read than 1.70 m, even though the two are identical.
