Handrail Height
Plan railing height, length and mounting posts for stairs.
About Handrail Height
The stair run gains a foot of extension at each end, and a post is placed at the ends plus every six feet along the run. Most codes set rail height from 34 to 38 inches above the nosing, so selecting the target up front keeps the rail code-friendly.
Formula
Handrail Height
Rail length = stair run + 2 ft of extensions; posts every 6 ft
- extensions
- Extra rail that reaches beyond the top and bottom steps
Worked example
With the default values below, Handrail Height returns Rail Height of 36. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Stair runminimum 1 ft
- 12 ft
- Rail heightone of Low 34 in, Standard 36 in, Tall 38 in
- Standard 36 in
Results
- Rail Height
- 36 in
- Rail Length
- 14.0 ft
- Mounting Posts
- 4
Step by step
- 1Values used
- 2Handrail Height
- 3Rail Height= 36 in
- 4Rail Length= 14.0 ft
- 5Mounting Posts= 4
Assumptions and limits
- The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 1 decimal place, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Handrail Height calculated?
Rail length = stair run + 2 ft of extensions; posts every 6 ft The stair run gains a foot of extension at each end, and a post is placed at the ends plus every six feet along the run.
Why does Handrail Height matter?
Most codes set rail height from 34 to 38 inches above the nosing, so selecting the target up front keeps the rail code-friendly.
What values do I need to enter?
This calculator takes 2 inputs: Stair run, Rail height. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.