How to Use the Drawing Scale Converter
Architectural and engineering drawings can't be drawn at real-world size, so they're scaled down (or up) by a fixed ratio. A scale of 1:100, for example, means every inch on the drawing represents 100 inches in real life. Enter a drawing measurement and scale to get the real-world length, or enter a real-world measurement to find the equivalent drawing length.
If you're new to reading drawings, a scale label like 1:50 or 1:200 alone can be hard to picture in real terms. Measure a length on the drawing with a ruler, plug it into this calculator, and get the actual dimension instantly — handy for reviewing construction drawings or planning a renovation. If your scale isn't listed, choose 'Custom' and enter the denominator.
Frequently Asked Questions
A length of 1 inch on the drawing equals 100 inches in real life. The larger the second number, the more the drawing is scaled down from actual size.
Select 'Custom' and enter the denominator of your scale (for example, enter 250 for a 1:250 scale) to get the same calculation.