Floor Plan Scale Converter
Convert between a measurement on a scaled plan and the real distance it stands for — metric ratios like 1:50 and 1:100, and imperial scales like 1/4″ = 1′.
Converted measurement
On a 1:50 plan, one unit on paper stands for 50units in the room. Imperial scales convert to the same kind of ratio — 1/4″ = 1′ is 1:48. Always sanity-check against a known dimension on the drawing.
Read any plan with confidence
Floor plans are drawn to scale so a whole room fits on a page, but that means every measurement you take off the paper has to be scaled back up to reality. Get the ratio right and you can lift real dimensions straight from an estate-agent plan, a rental listing, or your own sketch — and draw your own to scale in return.
Metric ratios and imperial architectural scales are two ways of saying the same thing, and this tool handles both. Whichever you use, sanity-check a converted length against a dimension you already know before you rely on it.
Frequently Asked Questions
How do I convert a measurement on a floor plan to the real size?
On a plan drawn at 1:N, one unit on the paper stands for N units in the real room, so you multiply the measured length by N. A line that measures 40 mm on a 1:50 plan represents 40 × 50 = 2000 mm, or 2 metres. This converter does that in both directions.
What does a scale like 1:50 or 1:100 mean?
It's a ratio between the drawing and reality. At 1:50, the real room is 50 times bigger than the drawing; at 1:100, it's 100 times bigger. A larger denominator means a smaller, more zoomed-out drawing. Common scales for room and floor plans are 1:50 and 1:100 in metric.
How do imperial architectural scales work?
An imperial scale such as 1/4" = 1'-0" means a quarter-inch on the drawing represents one real foot. Because a foot is twelve inches, that's a ratio of 1:48. The converter offers the common architectural scales and turns them into the same kind of ratio behind the scenes.
How do I go from a real dimension to the drawing?
Divide the real distance by the scale denominator. To draw a 3-metre wall at 1:50, you'd draw 3000 mm ÷ 50 = 60 mm. Switch the converter to "real distance → drawing measurement" and it does the division for you.
Why doesn't my printed plan match the scale?
Printing or photocopying often rescales a drawing, so the stated scale may no longer hold on paper. Always check against a known dimension — a scale bar or a labelled wall — before trusting a measured length, and prefer the figured dimensions written on the plan over anything you scale off it.
A general conversion from the scale and measurement you enter. Printing can rescale a plan — always verify against a known dimension or the figured dimensions written on the drawing.