Map Scale Calculator
Convert distances measured on a map to real distances using its scale.
About the Map Scale Calculator
Enter the map's scale (the number after 1:), the distance you measured on the map and whether you measured in centimetres or inches. The calculator gives the real distance in kilometres or metres and in miles.
A scale of 1:50,000 means 1 unit on the map equals 50,000 of the same units on the ground, so 1 cm = 500 m. Topographic maps are often 1:25,000 or 1:50,000; Indian cadastral (village) maps are commonly 1:4,000 or 1:8,000.
The formula
Real distance = map distance × scale
Worked example
4.2 cm measured on a 1:50,000 map
- 4.2 × 50,000 = 210,000 cm
- = 2.1 km
- = 1.305 miles
Things to keep in mind
- Gives straight-line distance on the map; walking routes over hills are longer.
Questions people ask
What's a large-scale map?
One with a small ratio like 1:1,000, showing a small area in detail.
How do I measure curves?
Use a string along the route, then measure the string.