Measure once, divide evenly
Enter the finished-floor rise. Auto mode chooses a practical count and divides the height into equal risers.
⌁ Build-ready layout
Stair Stringer Calculator
Turn a floor-to-floor measurement into an even stair plan. See every tread, the supporting stringer, cut dimensions and planning checks update instantly.
Live scaled drawing Imperial + metric Workshop summary
Stair dimensions
INPUTSfinished floor to finished floor
ft
in
used to choose riser count
in
horizontal step distance
in
in
in
Installation
OPTIONSStringer layout
14 equal risers · 13 treads
Stringer cut profile · live scale
Finished tread capsCut stringer bodyMeasured dimensions
7 11/16 inActual riser
11 ft 4 1/2 inTotal run
14 ft 6 1/16 inStringer length
38.3°Stair angle
Cut & layout schedule
| Risers / treads | 14 / 13 |
| Unit rise | 7 11/16 in |
| Unit run | 10 1/2 in |
| Bottom riser cut | 6 11/16 in |
| 2R + G comfort check | 25 7/8 in |
| Suggested stock length | 15 ft 6 1/16 in |
Bottom cut subtracts tread thickness so finished riser heights stay even. Suggested stock adds 12 in (304.8 mm) for end cuts and attachment; verify actual bearing details.
Planning checks
Reference checks are a planning aid, not approval. Local code, framing, species/grade, span, connectors and inspection requirements control.
See the whole stair
The side elevation shows treads, risers, support stringer, pitch, total rise and total run at a glance.
Review before cutting
Compare the result with a planning profile, then copy or print a compact layout schedule for the workshop.
From site measurement to first cut
A reliable layout starts with finished dimensions—not rough framing guesses.
1
Measure total riseMeasure vertically from the finished lower floor to the finished upper floor or deck surface.
2
Set tread and finish detailsEnter horizontal going, nosing projection and the actual thickness of the finished tread material.
3
Transfer the repeated triangleLay out each unit rise and unit run with a framing square. The final bottom rise is shortened by the tread thickness.
Stair anatomy
Know what each measurement controls in the drawing and on the finished stair.
Riser
The vertical height from the top of one finished tread to the next.
Going / run
The horizontal distance from one riser face to the next.
Nosing
The part of a tread that projects beyond the riser below.
Stringer
The sloped structural member that carries the stair treads and risers.
How the layout is calculated
risers = round(total rise ÷ target rise) · actual rise = total rise ÷ risers · treads = risers − 1 · total run = treads × going · stringer = √(rise² + run²)
Terminology and planning references: Calculator.net stair guide, Decks.com stair calculator, and VibeCalc stringer guide.
What the stock length means
The result uses the straight line between the stair endpoints, then adds 12 in (304.8 mm) as working allowance.
- It is an estimating length, not a structural specification.
- Available board sizes and actual attachment cuts may require more stock.
Common layout questions
Why is the bottom riser cut shorter?
The first cut is reduced by the tread thickness. Once the finished tread is installed, the walking-surface-to-walking-surface rise matches the other steps.
Why are there fewer treads than risers?
The upper floor or deck acts as the final walking surface. A typical stair therefore has one fewer built tread than vertical rises.
Should I use auto or manual riser count?
Auto mode is useful for finding an even layout near your target height. Manual mode lets you test a specific whole-number count while keeping every riser equal.
Can I cut directly from this drawing?
Use it as a planning and layout aid. Confirm finished dimensions on site, local code, stringer capacity, connection details and material defects before cutting.
Cut summary copied