Stair Calculator

Design safe and code-compliant stairs with precise measurements

Stair Measurements
inches
Vertical distance from floor to floor
inches
Horizontal distance (optional - will be calculated if empty)
inches
Width of each step
inches
Building code typically limits to 7¾"
inches
Building code typically requires at least 10"
Stair Calculation Results

Number of Steps

0

Riser Height

0"

Tread Depth

0"

Total Run

0"
Safety & Code Compliance

Stair Summary

Total Rise

0"

Total Run

0"

Stair Angle

Stair Type

-
Stair Visualization
Diagram showing riser height and tread depth proportions
Building Code Requirements
Parameter Recommended Your Stairs Compliance

Detailed Measurements

Complete measurements for building your stairs

Step # Riser Height Tread Depth Step Height Step Depth
Stair Building Tips
  • Always check local building codes before construction
  • Keep riser height consistent for safety
  • Use the 7-11 rule (7" riser, 11" tread) as a guideline
  • Ensure adequate headroom (at least 6'8")
  • Install handrails for stairs with 4+ risers
  • Consider non-slip surfaces for treads
Stair Formulas

Number of Steps: Total Rise ÷ Riser Height

Riser Height: Total Rise ÷ Number of Steps

Tread Depth: Total Run ÷ (Number of Steps - 1)

Stair Angle: atan(Riser Height ÷ Tread Depth)

Blondel's Formula: 2×Riser + Tread = 24-25 inches

For comfortable stairs: Riser × Tread ≈ 70-75 inches