Scale Converter – Convert Drawing and Map Scales Online
Convert between map or model scale and real-world size.
About the Scale Converter
What is the Scale Converter?
A scale converter turns a measurement taken on a map or model into the real-world distance using the scale ratio.
Why use this calculator?
Maps, architectural drawings and scale models all use a ratio such as 1:100, and converting measured lengths by hand is tedious and error prone.
How to use it
- Enter the length you measured on the map or model.
- Enter the scale as 1 : N (for example 100 for 1:100).
- Read the real-world length.
Formula
Real length = measured length × N.
A scale of 1:50,000 (common on maps) means 1 cm on paper equals 50,000 cm, or 500 m, in reality.
Frequently Asked Questions
What does a 1:100 scale mean?
Every 1 unit on the drawing or model represents 100 of the same unit in real life.
How do I read a map scale of 1:50,000?
One centimetre on the map equals 50,000 centimetres, or 500 metres, on the ground.
How precise are the conversions?
Conversions use standard, internationally defined factors and are rounded for display. They are accurate to the number of digits shown.
Can I convert back and forth without losing accuracy?
Yes. Enter the original value to get an exact inverse conversion; avoid chaining rounded results if you need maximum precision.
Which measurement system is used?
Both metric (SI) and US customary / imperial units are supported and clearly labelled.
Is this calculator free to use?
Yes. Every calculator on this site is completely free, with no hidden fees, no subscriptions and no limits on how many times you can use it.
How accurate are the results?
We use standard, widely accepted formulas and calculate in your browser using double-precision arithmetic. Results are rounded for readability, so treat them as reliable estimates rather than a guarantee. Real-world factors can vary the true figure.
Can I add this calculator to my own website?
Yes. Open this calculator page and use the "Add to your website" box in the sidebar to copy a ready-made iframe snippet, then paste it into any HTML page.
Does it work on a phone or tablet?
Yes. The layout is fully responsive, so it works on desktops, laptops, tablets and mobile phones, and every input adapts to touch screens.
Is the information I type kept private?
Yes. All calculations run locally in your browser. Nothing you enter is uploaded, stored or shared with anyone.