Stair Calculator & Stringer

Stair Calculator & Stringer works out a stair from three numbers: total rise, max riser height and tread depth. Type them in feet, inches and fractions, the way you measured them. A side view of the stair redraws as you go. Say the rise is 9′ 0″, the max riser 7 3/4″ and the treads 10″. You get 14 risers at 7 11/16″, with the exact 7.714″ underneath. That's 13 treads, a total run of 10′ 10″, a stringer of about 14′ 1″ and a 37.6° angle. The bottom riser gets cut shorter by the tread thickness, and the app shows that cut too. The straight stair costs nothing. It works offline and you don't need an account. What the stairs calculator shows • A side view with total rise, total run, stringer and angle, drawn to scale from your numbers • Riser count, riser height, tread count, total run, stringer length and the bottom riser cut • Set a max riser and let the app pick the riser count, or set the count yourself • Tread thickness, floor finish and nosing sit in a Details sheet with sensible defaults • A plain note compares your riser and tread with the limits you set • Common comfort rules of thumb, like two risers plus a tread • A feet, inch and fraction keypad, or mm, cm and m. Round to 1/8″, 1/16″ or 1/32″ • A dark theme, and an outdoor light theme for bright sun Pro, one time $4.99 • Stringer layout: the board with numbered framing square marks. Rise goes on the tongue and run on the blade. You see the step along the board, the bottom riser cut and the cut at the upper floor • The stair layout also counts stringers for your stair width and picks a stock length to buy. It checks the wood left under each notch on a 2×10 or a 2×12 • L and U stairs with a landing: a plan view and a side view. The risers split between the two flights, or you set the split. You get landing size and height and a headroom note • Balusters: the count and the exact even gap for a rail section, starting from a 4″ max gap • Projects: save a stair with its results, rename it, copy it and open it again later. Saved numbers stay as you saved them • Share PDF: drawings, results, stringer layout and a cut list for your crew • No ads It's handy for basement stairs, deck stairs, porch steps and attic stairs. Every Pro screen shows a sample first, so you know what you get before you pay. Pay once There's no subscription. Pro is bought through Google Play, and you can restore it on a new phone with the same Google account. About ads The free version shows one small banner at the bottom of the Stairs, Projects and Settings screens. It never covers your numbers, and Pro removes it. Results are estimates for planning. Notes compare your stair with the limits you set and with common US values. They're not a code approval. Check your local building code and talk to a qualified builder before you cut.

First release. Enter total rise, max riser and tread depth in feet, inches and fractions and get risers, treads, run, stringer length and angle with a live side view. Pro adds the stringer layout, L and U stairs with landings, balusters, saved projects and a PDF.