What do I need to enter?

The total floor-to-floor height in inches, your target riser height and the tread depth.

What results does the staircase calculator give?

The number of stair steps with all risers exactly equal — the mark of a safe staircase — plus the riser height and tread depth.

Blondel's formula: 2 times riser plus tread should be 23 to 26 inches for a comfortable stair.

Yes. It is free, needs no signup, and runs in your browser. Confirm local building codes and space limits.

Calculate stair steps, riser height and tread depth from total floor height.

Total floor to floor height (in)

Target riser height (in)

Tread depth (in)

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Enter the total floor-to-floor height in inches.
Enter the target riser (usually 6.5-7.5 inches) and tread depth (usually 10-11 inches).
The step count is chosen so all risers are exactly equal — that is the mark of a safe staircase.

Note: Blondel formula: 2 x riser + tread = 23-26 inches is considered comfortable. Confirm local building codes and space limits.