One kilometer in every other length unit on this site
- Millimeters1,000,000 mm
- Centimeters100,000 cm
- Meters1,000 m
- Inches39,370.079 in
- Feet3,280.8399 ft
- Yards1,093.6133 yd
- Miles0.62137119 mi
Kilometers to centimeters table
| Kilometers (km) | Centimeters (cm) |
|---|---|
| 1 | 100,000 |
| 2 | 200,000 |
| 3 | 300,000 |
| 4 | 400,000 |
| 5 | 500,000 |
| 6 | 600,000 |
| 7 | 700,000 |
| 8 | 800,000 |
| 9 | 900,000 |
| 10 | 1,000,000 |
| Kilometers (km) | Centimeters (cm) |
|---|---|
| 12 | 1,200,000 |
| 15 | 1,500,000 |
| 20 | 2,000,000 |
| 25 | 2,500,000 |
| 30 | 3,000,000 |
| 40 | 4,000,000 |
| 50 | 5,000,000 |
| 60 | 6,000,000 |
| 75 | 7,500,000 |
| 100 | 10,000,000 |
Where you need kilometers in centimeters
This conversion comes up when a real distance has to shrink onto paper or a screen. To draw a 3 km road on a 1:50,000 map, convert it to centimeters (300,000 cm) and divide by 50,000, which gives 6 cm on paper. Model makers do the same with their own scales.
Physics problems written in the older CGS system (centimeter, gram, second) also ask for distances in centimeters, so a kilometer value has to be scaled up before it goes into a formula.
School map exercises usually start from this conversion too, since a scale like 1:200,000 is easier to understand once the kilometers are written out in centimeters.
Five places to the right
- 0.5 km = 50,000 cm
- 1.2 km = 120,000 cm
- 5 km, a 5K run, = 500,000 cm
- 42.195 km, a marathon, = 4,219,500 cm
Avoiding zero-count errors
With five zeros involved, a slip of one place gives an answer ten times too big or too small. A quick sense check helps: a kilometer is roughly a twelve-minute walk, and a centimeter is about the width of a fingernail, so the answer should always be a very large number.
Scientific notation keeps it tidy: 1 km = 10⁵ cm. The cm to km page runs the same factor in reverse, and km to m handles the more common step.
Spreadsheets can hide the problem too. A cell formatted to two decimals may show 0.00 for a centimeter value converted to kilometers, so widen the format or switch to scientific notation before you trust a result. When a figure feels wrong, convert one step at a time, kilometers to meters and then meters to centimeters, and compare.
Writing the factor as a fraction, 100,000 cm per 1 km, also lets you cancel units on paper and see at once that the answer must be in centimeters.
Km to cm questions
How many cm is 2 km?
2 × 100,000 = 200,000 cm.
What is 0.01 km in centimeters?
0.01 km is 10 m, which is 1,000 cm.
How do I write 1 km in centimeters with powers of ten?
1 km = 10⁵ cm. The kilometer is 10³ m and the centimeter is 10⁻² m, so the ratio is 10³ ÷ 10⁻² = 10⁵.
How many millimeters are in a kilometer?
1,000,000 mm, ten times the centimeter figure.