Drawing Scale Converter
AvailableConvert a length on a scaled drawing to real size, or the other way round.
Use the calculator
The numbers below are examples. Replace them with yours. Everything is worked out in your browser.
About this calculator
Architectural and engineering drawings are drawn to a scale such as 1:50 or 1:100. Convert a length you measure on the drawing to real size, or find how long something real will be on paper.
How it works
- Real length is the drawing length times the scale number.
- Drawing length is the real length divided by the scale number.
- Results are shown in millimetres, metres and feet.
This is a preliminary estimate for planning and shopping lists. It is not a structural design, a safety check or a building-code approval. Ask a qualified professional before you build.
Common questions
What does 1:100 mean?
One unit on the drawing stands for 100 of the same unit in real life, so 45 mm on the drawing is 4500 mm, or 4.5 m, in reality.
Can I trust a printed scale?
Printing can stretch or shrink a drawing. Check against a dimension written on the drawing.
Estimates only. Check important numbers before you rely on them.
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