Map scale calculator
Convert between map distance and ground distance for any scale such as 1:50000, in centimeters, kilometers, meters or miles, with a comparison table of common scales.
Runs in your browserEvery computation happens in your browser — your data never leaves this device.
Scale and distance
A scale of 1:N means 1 cm on the map equals N cm on the ground. Exact constants are used: 1 mile = 1609.344 m, 1 inch = 2.54 cm.
Conversion
2.000 km · 2000.0 m · 1.243 mi
1 : 50000 — 1 cm on the map = 0.5 km on the ground
1:500 → 0.020 km
1:1000 → 0.040 km
1:2000 → 0.080 km
1:2500 → 0.100 km
1:5000 → 0.200 km
1:10000 → 0.400 km
1:25000 → 1.000 km
1:50000 → 2.000 km
1:100000 → 4.000 km
1:200000 → 8.000 km
1:500000 → 20.000 km
1:1000000 → 40.000 km
What this tool does
- Estimate a trip from a paper map: measure the distance in centimeters and convert it with a scale such as 1:50000.
- Plan a hike or ride the other way round — turn a 5 km leg into centimeters so you can mark waypoints on the map.
- Compare how much detail different scales give: the same map length means very different ground distances at 1:10000 and 1:50000.
- Double-check a distance against a map or a GIS drawing instead of assuming “1 cm on the map” means one kilometer on the ground.
Example
Input
Scale 1:50000, distance on the map 4 cm
Output
Ground distance 2.000 km · 2000.0 m · 1.243 mi; scale 1 : 50000 — 1 cm on the map = 0.5 km on the ground
A scale of 1:50000 means 1 cm on the map equals 50000 cm, or 0.5 km, on the ground, so 4 cm is 2 km.
Frequently asked questions
What does 1:50000 actually mean?
One unit on the map equals 50000 of the same unit on the ground. Measure 1 cm and it is 50000 cm, or 500 m, in reality; measure 4 cm and it is 2 km. That is also why a larger scale (smaller denominator) shows more detail.
Is scale the same as scale accuracy?
No. The scale is the map-to-ground ratio, while scale accuracy is the ground distance represented by 0.1 mm on the map — 5 m at 1:50000. On such a map you cannot resolve differences smaller than that, however carefully you measure.
Why show meters, kilometers and miles at once?
Because habits differ: meters for hiking, kilometers for driving and miles for imperial maps. All three come from a single meter-based intermediate value, and 1 mile = 1609.344 m is an exact definition, so the results can never disagree.
Does it work with a digital map on my phone?
Yes, but confirm the scale first. Digital maps change scale as you zoom and normally show a scale bar; enter that scale, measure the on-screen distance in centimeters, and the result is the ground distance.
What range of scales is supported?
Denominators from 1 to 10000000. 1:10000000 is already close to a small-scale world map; anything larger falls outside normal mapping and the tool reports an error.
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