DIDIM stair calculator

Try every feature free for 14 days. After that, straight-stair auto calculation and the plan and section sketches stay free; everything else is a one-time purchase. Not a subscription.

A stair calculator for early design
Enter the floor height and floor build-up, and DIDIM works out the number of steps, riser and tread using the step rule (2h + l). It also gives landings, the floor opening length and the footprint, and shows them as hand-drawn plan and section sketches.

Features
• Auto mode aims for a 170 riser and 290 tread; adjust steps with −/+
• Checks: 2h + l (DIN 18065, 590–650 mm), difference from l − h and l + h targets, pitch
• Straight, L- and U-shaped stairs with flight split
• Landing interval and length, floor opening from headroom
• Hand-drawn plan and section sketches, saved or shared as images
• Manual mode: set steps and tread yourself
• Last 10 calculations saved
• Theory: Blondel's formula and step rules / Codes: stair dimensions by country
• mm or inches, English and Korean

Note
Results and sketches are references for early design. Always check compliance with your local building code.

Privacy
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