Plan-measuring guides

Short, practical reads on getting trustworthy numbers off a drawing — how calibration works, what drawing scales mean, and how to handle the messy cases like photos and unlabelled plans. Each one ends where you'd expect: measuring your own plan, free, in your browser.

• How to measure a PDF floor plan The step-by-step how-to: upload, calibrate against one known dimension, measure anything — plus why the stated scale can't be trusted on a screen, and what to do when the plan has no dimensions at all.
• Architectural scales explained Reference tables for 1:5 through 1:1250 and the imperial equivalents (¼″ = 1′-0″ ≈ 1:48), the conversion maths with worked examples, and how to use a scale bar.
• How to measure area on a plan Trace a polygon over any room, garden or plot and read m² or ft² — with inside-face vs footprint conventions and a flooring worked example, waste allowance included.
• Measuring from a photo of a plan When a phone photo is good enough, how to shoot one that measures well, and the cross-direction calibration check that catches perspective distortion.