Calculate stair risers, treads, total run, stringer length, stair angle, board length, and stair layout measurements. Use this stair stringer calculator for deck stairs, porch stairs, basement stairs, interior stairs, exterior stairs, and preliminary stair framing planning.
Riser count:
The calculator divides total rise by the target riser height and rounds to a practical whole number of risers.
Actual riser height:
The calculator divides total rise by the final riser count to estimate the actual height of each riser.
Total run:
The calculator multiplies tread depth by the number of treads, then adds top landing or layout offsets when entered.
Stringer length:
The calculator uses the stair rise and run as a right triangle to estimate diagonal stringer length.
A stair stringer calculator helps estimate stair layout measurements before cutting stringers or ordering material.
It can help compare risers, treads, actual riser height, tread depth, total run, stair angle, board length, stringer count, and material cost.
Your result shows estimated number of risers, number of treads, actual riser height, tread depth, total run, stair angle, stringer length, board length check, stringer count, stair width, and estimated material cost. These are planning estimates only.
Use the total rise and total run as a right triangle. The stringer length is the diagonal distance calculated with the Pythagorean formula.
Divide total rise by your target riser height and round to a whole number. Then divide total rise by that riser count to get the actual riser height.
For many stair layouts, tread count is one less than riser count because the upper landing acts as the final step. Some layouts may vary.
No. Final stairs should follow local code for maximum riser height, minimum tread depth, nosing, landing size, headroom, handrails, guards, lighting, and structural support.