Map Scale Calculator
This map scale calculator converts a length from the plan or map to real life and back, and finds the scale from two lengths. Example: 4 cm on a drawing at a scale of 1 : 50 is 2 m in reality.
Example: What do you want to calculate: Convert a length · Scale number (1 : …) 50 · Type of scale: Reduction (1 : x) · Convert from: Plan or map → reality · Length 4 · Unit: cm → Result: 4 cm on the plan is 2 m in reality (scale 1 : 50). Source: Wikipedia – Maßstab (Verhältnis). Updated: .
How it is calculated
The scale tells how much a drawing, map or model is reduced or enlarged compared with reality: 1 : 50 means 1 cm on the plan equals 50 cm in real life. The calculator converts lengths in both directions and finds the scale from two known lengths.
The formulas
With the scale number M (for 1 : M), reality = plan · M, plan = reality / M and M = reality / plan. Examples: 4 cm at 1 : 50 is 200 cm = 2 m; a room 4.5 m long is drawn 9 cm long at 1 : 50; 3.2 cm on a 1 : 25,000 map equals 800 m. For an enlargement such as 5 : 1, M = 0.2, so the drawing is five times as large as the original.
Areas and table
Areas change with the square: at 1 : 100, 1 cm² on the plan is 10,000 cm² = 1 m² in reality. The table shows the same length at common scales from 1 : 2 to 1 : 1,000,000, for example for building plans (1 : 50, 1 : 100), hiking maps (1 : 25,000) or road maps (1 : 200,000).
- The scale number has no unit; plan and reality only need to be converted to the same unit.
- The larger the number after the colon, the smaller and less detailed the depiction.
- For maps, 1 cm equals M / 100,000 km.
Frequently asked questions
How do you convert a scale?
Multiply the length on the plan by the scale number to get reality: 4 cm · 50 = 200 cm = 2 m. In the other direction divide the real length by the scale number.
How do you find the scale from two lengths?
Divide the real length by the length on the plan, both in the same unit. 5 m in reality and 2 cm on the plan give 500 cm / 2 cm = 250, so 1 : 250.
How does area change with a scale?
With the square: at a scale of 1 : M the area scale is 1 : M². At 1 : 100 a square of 1 cm² on the plan equals 1 m² in reality.
Sources and legal basis
As of: · Editorial policy
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