Stair Stringer Calculator
Approximates stringer length as hypotenuse × count; planning only.
Reviewed by MaterialNeeded Editorial Team, Editorial review for field workflows and ordering assumptions.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
How to use this calculator
Total rise and total run for one flight, number of stringers (usually 2–3).
What the math is doing
Stringer length ≈ sqrt(rise² + run²) × count.
Frequently asked questions
Code rise/run?
Verify comfort and code.
Open stringers?
Different stock layout.
Landings?
Add separate flights.
Engineering?
Critical structural element.