StructCalc logo StructCalc
Built with confidence

Construction calculator for stairs, rafters & framing.

The all-in-one calculator for stairs, rafters, railing & materials. Built for pros, on the job. Rafter length, stair stringers, baluster spacing, roof pitch, and right-angle verification — all solved instantly without manual math. Works fully offline.

Google Play

Free • 100% offline • No account • ft/in + metric

App Store — coming soon

Pixel 8 phone showing the StructCalc tools overview: rafter calculator, staircase, square check, flooring, baluster spacing and raked wall tools
12+
Calculators
100%
Offline Ready
Pro
Grade Accuracy
What's Inside

Every tool
you need.

Stair calculator

Calculate risers, treads, stringers, and stair layouts with professional-grade accuracy. Handles any rise and run combo.

Rafter & roof calculator

Precise cuts for common, hip, and jack rafters. Pitch, run, rise — solved instantly without the trigonometry headache.

Wall framing calculator

Stud layout, plate lengths and stud schedules for angled walls — in the Android app.

Get it in the app

Concrete & material calculators

Concrete volumes, board feet, flooring and paint coverage — in the Android app.

Get it in the app
Browser Demos

Free web
calculators.

Need a quick number from the browser? Try a few StructCalc demo calculators, then install the Android app for the full jobsite workflow.

Rise + run

Stair calculator

Check total rise, tread rise, tread run, stair angle and layout options.

Open calculator Roof framing

Rafter calculator

Calculate common rafter length, roof pitch, rise, run and overhang.

Open calculator Layout check

Square check

Find the expected diagonal and compare it with your measured diagonal.

Open calculator Materials

Concrete calculator

Slab, footing and column volumes with order volume and overage.

Open calculator
In Action

See it
work.

Designed for the job site — fast inputs, clear results, no fuss. Works fully offline. From roof framing and stair layouts to concrete estimates and baluster spacing, StructCalc handles the math so you can focus on the build.

Stair Calc
Stair calculator demo with rise, run and angle results
Stairs
Rafter Calc
Rafter calculator demo with rafter length and pitch diagram
Rafters
Balusters
Baluster spacing demo for railing layout
Balusters
Why StructCalc

Built for
offline jobsite work.

  • 01 Advanced framing calculators built for professionals
  • 02 Simplifies complex carpentry math instantly
  • 03 Accurate layouts for foundations, roofs & stairs
  • 04 Optimized for speed and efficiency on the job site
  • 05 Works fully offline — no signal needed
  • 06 Supports Metric and Imperial units
Available Now

Download
Free

Start calculating smarter. Free on Android, iOS coming soon.

Get on Google Play