StairSmith

The fastest stair calculator on iOS. Live diagram, instant code compliance, print-ready PDF cut sheet. No subscription, no ads, yours forever.

The stair calculator built for builders and DIYers.

Type your total rise. StairSmith equalizes the risers, draws the elevation diagram live, runs the building-code checks, and tells you what to cut instantly. No account, no cloud, no subscription.

HERO FEATURES

• Live elevation diagram — pinch, pan, tap any dimension to learn what it means. • Cut Sheet hero — riser height, code going, riser count, stringer length. Take it to the saw. • Lumber cheat sheet — number of stringers, treads, and risers, with stringer length rounded to the next standard 2×12. • Framing-square layout — "set tongue at 7", blade at 10"" with a beautiful, printable diagram on page 2 of every PDF. • Code compliance built in — IRC 2021, IBC 2021, NBC 2020, UK Part K, and Australia NCC. Pass/fail on riser, going, 2R+T, and headroom. Free handrail and guard reminders. • Print-ready PDF — elevation diagram, cut list, lumber list, framing-square layout, and disclaimer. AirDrop, email, or print directly.

DESIGNED FOR THE SHOP

StairSmith is built around the moment you're at the workbench, sawdust on your glasses, trying to remember what number to mark. Open the "Show at Saw" sheet — the diagram fills your screen, with the two numbers you need in giant monospace type. Slide the framing square down the board, mark, repeat.

WHY ONE-TIME PURCHASE

Every other stair calculator on the App Store is either subscription-hostile or ad-ridden. StairSmith is a one-time purchase. Yours forever. No upsells, no nag screens, no "Pro" tier locked behind a paywall.

FOR DIY HOMEOWNERS

First time building a flight of stairs? Tap the (i) on Total Rise and you'll get a 3-sentence explanation of how to measure it correctly so your stairs don't end up an inch off. Tap any "Cut Number" on the Cut Sheet hero to learn what it means. The app teaches you while you use it.

FOR PROS

Switch between IRC, IBC, NBC, Part K, and NCC with a tap. Switch between imperial (with fractional input) and metric (mm) instantly. Save unlimited projects locally. The PDF cut sheet is dense, professional, and ready to hand a permit reviewer or a trade partner.

PRIVACY

StairSmith collects nothing. No account, no cloud, no analytics, no tracking, no ads. Your projects live only on your device.

NOT INCLUDED IN v1.0 (coming): multi-flight stairs, winders, landings, and isometric view. Today it's straight single-flight stairs only, done extremely well.

Built in California, by a builder who got tired of subscription tools that disrespect their users.

Questions: support@cascinobuilders.com