Staircase Calculator
Work out the number of steps, total run and tread depth for a staircase from its total height and riser height.
Recent
Formula
How the calculation works
Enter the total floor-to-floor height, the riser height you want and the tread run for each step.
The tool divides the total height by the riser height and rounds up, because a staircase cannot end with a partial riser.
It then applies the comfort rule that tread depth equals two times the riser plus the run, and reports the total run and total rise of the flight.
Common mistakes
- Forgetting to round up the riser count, which leaves the last step short and makes the whole flight uneven underfoot.
- Ignoring the comfort rule, because a riser that is too tall for its tread feels steep and unsafe despite fitting the available space.
When to use it
- Use it while planning a building to fix the number of steps before the drawing is finalised.
- Use it to check whether an existing staircase is safe by comparing its riser and tread with the comfort rule.
Worked example
For a floor-to-floor height of 120 inches and a riser of 6 inches, you need 20 risers. With a run of 10 inches the tread depth is 22 inches and the total run is 190 inches.
Common questions
What is the comfort rule for stairs?
The comfort rule says twice the riser plus the tread run should be about 24 to 25 inches, which keeps each step easy and safe to climb.
Related tools
-
Brick Calculator
Estimate how many bricks a wall needs from its length, height and thickness, allowing for mortar joints and wastage.
-
Building Material Estimator for Cement, Rod and Sand
Gives a quick estimate of cement bags, steel rods and sand needed for a given volume of concrete, using per-cubic-metre rates you can adjust.
-
Home Construction Cost Calculator (Bangladesh)
Multiplies floor area by the cost per square foot and the number of floors to estimate total building construction cost in Bangladesh.
-
House Rent and Advance Calculator
Adds the monthly rent and service charge and works out the advance you pay up front when renting a flat.
-
Land Registration Cost Calculator (Bangladesh)
Adds stamp duty, registration fee and source tax on a property value to estimate the total cost of registering a land deed in Bangladesh.
-
Land Unit Converter (Bangladesh)
Converts land area between the units used in Bangladesh, including square feet, square metres, katha, bigha, acre and decimal.
-
Plaster Calculator
Estimates the cement, sand and water needed to plaster a wall from the area, thickness and mix ratio, including a wastage allowance.
-
Plot Price Calculator
Find the total price of a plot from its size in katha or shotangsho and the rate per unit.