StructCalc - Construction Calc

StructCalc is a construction calculator for stairs, rafters, concrete and framing. Built by a carpenter, it works fully offline with no account, supports both imperial and metric measurements.

Each tool asks only for what it needs. Solve a rafter or a square check from any two known values. Lay out stairs from total rise, balusters from post distance and target gap, concrete from shape dimensions. Results update as you type, with diagrams for stairs, rafters and square checks, plus history and pinned calculations for repeat layouts.

STAIR CALCULATOR
Enter total rise to compare fewer, ideal and more step options. Each option shows tread rise, tread run, total run and stair angle, with standard or flush mount. Use it for interior stairs, deck stairs and stringer layout checks.

RAFTER CALCULATOR
Common and hip rafters from any two of roof pitch, rise or run. Get rafter length, overhang length, hip run, hip angle and jack backing distance. Use it for roof framing, pitch checks and overhang layout.

CONCRETE CALCULATOR
Slab, round footing, circular slab, tube, curb and gutter, and stepped stairs. Enter dimensions once to get volume per item, total volume and order volume with 0, 5 or 10 percent overage, with optional weight. Imperial shows cubic yards and cubic feet, metric shows cubic meters.

BALUSTER AND RAILING LAYOUT
Equal gap and fixed gap modes for railings, fences and decks. Compare fewer, ideal and more baluster options with exact gap or end gap from post distance and baluster width.

SQUARE CHECK
Verify right angles for foundations, walls and framing. Enter any two sides of a right triangle to solve the third, with a live diagram. Use it for 90 degree angle checks and foundation diagonals.

WALLS, SURFACE AND QUANTITIES
Raked walls with top plate length, stud increment and a stud schedule with layout marks. Roof and wall surface with openings, overhangs and waste overage. Floating flooring with balanced rows, joint staggering and order area. Paint coverage with coats, openings, container count and purchase extra. Wood volume with board feet, liters, cubic volume and optional cost. Generic volume for common construction shapes. Measurement series for cumulative marks along footings, plates and joists.

JOB-SITE CALCULATOR
A feet inch fraction calculator with metric support, plus math and trigonometry functions for sine, cosine, tangent and square root. Type 4 ft 3 1/2 in directly without decimal conversion.

BUILT FOR THE JOB-SITE
Works fully offline. No account. Imperial and metric in one app. Live diagrams that update as you type. Calculation history with pinned results. Dark and light mode.

FOR CARPENTERS, FRAMERS, ROOFERS, DECK BUILDERS, CONCRETE CREWS AND DIY HOMEOWNERS.

No account. Analytics is anonymous with no advertising identifiers. Optional purchases are handled by Google Play. Contact structcalc.contact@gmail.com for support or data requests.

Built by a carpenter. For every builder.

Recent changes:
• Faster startup: StructCalc now opens up to 3x faster
• Snappier calculator: keypad presses respond instantly
• Easier-to-read keypad with larger, bold numbers and icons, stronger contrast, a red AC button and a clearer backspace key, in light and dark mode
• Fixed a result that could freeze half-faded after tapping "Use in" on the scratch pad
• Updated app engine and smaller, more efficient build for better stability