Pitch
Framing, roofing, and truss calculators
A stair that fits the total rise, a roof pitch you can say three ways, a roof counted in squares and priced from your own quotes, the board length of a truss skeleton, a deck counted in boards and fasteners, and a wall counted in studs, plates, and sheets. Those counts are not a structural design.
Stair Calculator
Stair calculator for rise, run, riser height, and landings. Checked against IRC R311.7. The stringer cut is a separate tool.
Roof Pitch Calculator
Roof pitch calculator. Rise per 12, degrees, percent, and the rafter multiplier, from a rise and run or a measured angle.
Roofing Calculator
Roofing calculator for squares, shingle bundles, underlayment, drip edge, and hip and ridge. Uses the pitch multiplier.
Truss Calculator
Truss calculator for king post, Fink, and Howe board lengths. Geometry only. A truss has to be engineered.
Deck Calculator
Deck calculator for board, joist, and fastener counts. It does not size a joist or a beam and it does not check a span.
Framing Calculator
Framing calculator for wall studs, plates, header lengths, and sheathing sheets. Counts and cut lengths only. It does not size a header.
Roofing Cost Calculator
Roof replacement cost from area, tear-off, and prices you type. Example prices are not a quote or a national average.
Beam Calculator
Educational deflection and span check only. Not a structural design or sizing tool. Do not use this to size or approve a load-bearing beam — follow the IRC, AWC/AISC provisions, and a licensed structural engineer.
Plywood Calculator
Plywood and OSB sheet count from area, openings, and waste. It does not select grade, span rating, or structural thickness.
How these calculators work
The stair calculator divides the total rise into equal risers at or under the maximum you set. The default maximum is IRC R311.7.5.1, 7¾ inches, and the tread check is R311.7.5.2, 10 inches. A flight that would rise more than 151 inches is flagged for a landing. Each extra flight adds a 36-inch straight landing to the run, from R311.7.6. The stringer length here is one flight. The woodworking stringer calculator cuts that flight, including nosing and throat.
Roof pitch is the same triangle as a rafter. Rise ÷ run × 12 is the pitch. Degrees are arctan of the slope. Percent is the slope times 100. The rafter multiplier is the hypotenuse of 1 and the slope, so a 6/12 is √1.25 = 1.118. Measure a rise and a run, or enter an angle, and the other three follow. The rafter calculator takes the rise-per-12 figure and a span. The roofing calculator multiplies the footprint by that same factor, then counts squares, bundles, underlayment, drip edge, and hip-and-ridge cap. The roofing cost page uses that area and the prices you type. It is not a bid.
The truss calculator uses that same multiplier for the top chord, then adds the webs of a king post, a four-panel Fink, or a four-panel Howe. It reports board lengths. It does not check a load, a span rating, or a plate. A truss has to be engineered. Order it from a truss manufacturer or ask an engineer.
The deck calculator counts boards, joists, and fasteners. Boards run across the joists. Joists include both ends, and the last bay is shorter when the width does not divide evenly. It does not size a joist or a beam and it does not check a span. IRC R507, AWC DCA 6, and the local building department decide the lumber.
The framing calculator counts studs, plate pieces, header lengths, and sheathing sheets for a wood wall. Layout studs run the whole wall. Openings add kings and jacks. It does not size a header or a stud, and it does not check the spacing against a load. IRC R602 and Table R602.7 are where those rules live. The beam page is an educational deflection check, not a size. The plywood page counts sheets. It does not pick a span rating.