How does a drawing scale work?
A scale like 1:50 means one unit on the drawing equals 50 of the same units in real life. So 30 mm measured on a 1:50 plan is 30 × 50 = 1500 mm (1.5 m) in the building. This tool does that multiplication (and the reverse) for any metric or imperial scale you enter.
Does it handle imperial architect scales like 1/4″ = 1 ft?
Yes. Choose imperial and pick a common architect or engineer scale (3/4″, 1/2″, 1/4″, 1/8″ = 1 ft, or 1″ = 20 ft, 50 ft and so on). The calculator converts your measured inches to real-world feet and inches, and back again.
Is anything uploaded?
No. This is a plain calculator that runs entirely in your browser on your own device. There is no file, nothing is sent to a server, nothing is stored, and we never see your numbers. Safe to use on confidential project work.
Why is my on-screen measurement off?
A printed or PDF sheet is only accurate at its intended paper size. If a drawing was printed to fit a smaller page, or you measured on a zoomed screen, the ruler distance no longer matches the stated scale. Measure on the sheet at its true print size, or open the file in a tool that shows real units. For opening and marking up heavy CAD drawings, that is what the Ncored desktop app is built for.