About Easy Scale Calc

Why this exists

Easy Scale Calc is built by a product designer and 3D-printing hobbyist. Scale math comes up constantly in that kind of work — converting caliper measurements into CAD, working out slicer percentages, checking whether a downscaled STL still has printable wall thickness — and the existing online converters handled it badly: one direction only, single units, no fraction input, and a lot of ads between you and the answer.

This one is designed around how the math actually gets used:

• Bidirectional — type in any field and the others update. No mode switches.
• Mixed units are the normal case — plans are imperial, printers are metric, and the calculator doesn’t care.
• Fraction input — rulers say 3/8″, so 3/8 and 10 1/2 both work.
• Presets for common scales — 1:35, 1:48, 1:72, HO, N, 28mm, and the rest are one tap.
• Fast and unobstructed — the tool loads instantly and nothing covers it up.

How it works

Everything runs in your browser. No account, no install, free to use. Saved calculations stay in your browser’s local storage — they never touch a server — and can be exported to CSV or PDF from the Workbench History panel.

The scale reference pages collect the ratios, percentages, and dimensions that otherwise get looked up over and over, each with a calculator preloaded for that scale.

Contact

Bug reports, feature requests, and preset suggestions are all welcome — get in touch.