Example 1
- Total rise: 2.8 m
- Number of steps: 16
Step height: 17.50 cm
What riser height is 2.8 m and 16 steps? 2.8÷16 = 17.50 cm.
Stair Calculator
Enter total rise and the number of risers. The calculator divides height by the count and shows centimeters. A 2.8 m storey and 16 risers is 17.50 cm. At 3.0 m and 17 steps you get 17.65 cm.
Results
Total rise (m), Number of steps and Tread depth (cm). The result shows up here.
Riser height is a key comfort parameter for the flight. Related: 3-4-5 proportion, slope percent.
How the results are calculated
H2.8 m
n16
h17.50 cm
The stair calculator finds one riser height. The formula is h = H ÷ n, where H is total rise and n is the riser count. Optionally it shows Blondel 2h + s.
A 2.8 m storey and 16 risers is 17.50 cm. At 3.0 m and 17 steps the result is 17.65 cm. A lower 2.65 m ceiling and 15 steps is 17.67 cm. On the same 2.8 m: 15 risers give 18.67 cm, and 17 give 16.47 cm.
Enter total rise in the header unit, for example 2.8, and the riser count. Tread depth in centimeters is optional. A comma in 2.8 works the same as a period.
A square landing is the 3-4-5 proportion page. Driveway slope is a percent, not a riser. Concrete for treads lives on the concrete-volume page.
A tall riser wears you out on daily trips; a short one lengthens the flight. A common comfort band is about 15–20 cm. With a 29 cm going and 17.50 cm, Blondel is 64 cm.
Enter 2.8 and 16, click Calculate — you should get 17.50 cm. Then 3.0 and 17: 17.65 cm.
How to use this calculator
- Enter total rise in the header unit, for example 2.8 from finished floor to finished floor.
- Enter the number of steps, for example 16. That is risers, not landings.
- Leave tread depth empty when height alone is enough. Blondel 2h+s appears with depth.
- Click Calculate. 2.8 m and 16 steps give 17.50 cm. 3.0 m and 17 give 17.65 cm.
- If the result sits outside 15–20 cm, change the step count and compare variants.
Formula
h = H ÷ n
Blondel (optional): 2h + s
H is total storey rise, n the riser count, h one riser height, s the tread going. 2.8 m ÷ 16 = 0.175 m = 17.50 cm. With a 29 cm going: 2 × 17.50 + 29 = 64 cm.
h and Blondel
2.8 m and 16 risers is 17.50 cm. 3.0 m and 17 steps is 17.65 cm. A comfort band is usually 15–20 cm. Blondel 2h+s at 17.50 cm and 29 cm is 64 cm.
- H
- Total storey rise. 2.8 m with 16 risers is 17.50 cm.
- n
- Riser count. On 2.8 m: 15 → 18.67 cm, 16 → 17.50 cm, 17 → 16.47 cm.
- h
- One riser height. 17.50 cm at 2.8 m and 16; 17.65 cm at 3.0 m and 17.
- 2h+s
- Blondel check. At 17.50 cm and a 29 cm going the result is 64 cm (band 60–65 cm).
Example scenarios
Example 2
- Total rise: 3.0 m
- Number of steps: 17
Step height: 17.65 cm
3.0 m and 17 risers → 17.65 cm. Still inside the 15–20 cm band.
Example 3
- Total rise: 2.65 m
- Number of steps: 15
Step height: 17.67 cm
2.65 m and 15 risers → 17.67 cm. Lower ceiling, similar step height.
Example 4
- Total rise: 2.8 m
- Number of steps: 15
Step height: 18.67 cm
2.8 ÷ 15 ≈ 0.1867 m → 18.67 cm. Higher than 16 risers on the same storey.
Example 5
- Total rise: 2.8 m
- Number of steps: 17
Step height: 16.47 cm
2.8 ÷ 17 ≈ 0.1647 m → 16.47 cm. A lower riser and a longer run at the same height.
Example 6
- Total rise: 2.8 m
- 16 risers
- Going 29 cm
17.50 cm · Blondel 64 cm
2 × 17.50 + 29 = 64. A common Blondel band is about 60–65 cm.
Related calculators
Frequently asked questions
How do I calculate riser height from total rise and the number of steps?
Divide total rise by the number of risers. 2.8 m and 16 steps → 2.8÷16 = 0.175 m = 17.50 cm. A common comfort band is about 15–20 cm.
What riser height do 2.8 m and 16 steps give?
17.50 cm. At 3.0 m and 17 risers the result is 17.65 cm. Both sit in the roughly 15–20 cm comfort band.
Is this a stair stringer or landing calculator?
No. This page reports one riser height. Stringer cut lists, L-shaped runs, and landings are outside this tool.
Does the result replace a stair design or permit drawing?
No. It is a quick riser-height estimate plus an optional Blondel 2h+s comfort check. Local codes and the designer set the final sizes.
Is this a free stair calculator?
Yes. Enter total rise and the riser count (and optional tread depth) and you see centimeters per step at once. No account required.
How is riser height calculated?
The calculator divides total rise by the number of risers. A 2.8 m storey and 16 risers is 17.50 cm. At 3.0 m and 17 steps the result is 17.65 cm.
What riser height feels comfortable?
Usually about 15–20 cm. On the same 2.8 m: 15 risers give 18.67 cm, and 17 risers give 16.47 cm. The project and local codes decide the final limit.
What does Blondel 2h+s do?
It adds two riser heights and the tread going. At 17.50 cm and a 29 cm going the check is 64 cm, inside the usual 60–65 cm band. It is a comfort check, not a building code.
Is tread depth required?
No. Height comes from total rise and the riser count. Depth only shows Blondel. An empty field leaves 17.50 cm at 2.8 m and 16 risers unchanged.
Which unit should I use for rise?
The header unit, usually meters (or feet in US units). 2.8 means a storey in meters. Entering 280 would be read as 280 m.
Does the result replace a stair design?
No. The calculator shows a quotient of two fields. Flight width, a handrail, landings, and the code stay outside this tool.
How do I fix a riser that is too high?
Increase the riser count if the layout allows. On 2.8 m, moving from 15 to 16 risers lowers the height from 18.67 cm to 17.50 cm.
How is this different from the 3-4-5 proportion?
Here the result is one riser height. The 3-4-5 page checks a right angle, for example on a landing. Driveway slope is a separate percent tool.
Does a comma in 2.8 work?
Yes. A comma and a period are the same rise. At 16 risers the result stays 17.50 cm.
Can I use this for outdoor stairs?
Yes, as a quick riser-height estimate. Outdoors you also weigh material, freeze, and slip — outside this calculator.
Knowledge sources
Riser height is H ÷ n. Blondel 2h+s is a classic comfort check for a flight. Length units below from NIST.
Page updated October 12, 2026.