Converters & essentials
Plan Scale Converter
Measure a wall on a scaled drawing and get its real length - or work backwards to find what a real dimension should measure on the plan.
Calculator
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How it works
At 1:50, every millimetre on paper is 50 mm in the building. Enter the scale plus either the on-plan measurement or the real one, and the tool fills in the other.
Frequently asked questions
What does a 1:100 scale mean?
One unit on the drawing equals 100 of the same unit in reality - 10 mm on paper is 1 m built. Floor plans commonly use 1:50 or 1:100; location plans use 1:1250.
How do I measure from a PDF plan?
Check the plan has a scale bar and print at 100% (no "fit to page"). Then measure with a ruler and convert here. If you scanned the room with RoomPlot instead, dimensions are already real.