Stair stringer layout tool

Measure the rise, pick your lumber, and mark the board. The layout redraws as you type.

Total rise

From the landing surface to the top of the finished deck or floor. Fractions like 36 1/2 work.

Set the run by

Available total run

Face of the deck to where the bottom step lands.

Top of the stair

Nosing

Below: the deck is the top step. Nosing is the tread overhang past the riser.

Tread thickness

Riser board

Use 0 for open risers.

Stringer lumber

Riser height: —
Tread depth: —
Risers: —
Treads: —
Pitch: —
Throat: —
Bottom drop: —
Cut length: —

Multi-Stringer Build Pack · Live Preview

Full stair framing cut list, tread rip widths & lumber shopping sheet

Edit width & board prices ↓

Stringer layout 3 stringers at 17 1/4 in o.c. 36 in stair width · 16 in max spacing

Tread & riser cut list 4 treads · rip width locked Exact crosscut length + back board rip

Lumber shopping list 3 × 2x12 · 2 × 5/4x6 boards Est. material total: $184

Free: 1:1 printable stringer marking template, framing-square steps & 3D view. Build Pack ($4.99 · 7-Day Pass): Multi-stringer spacing plan, exact tread rip widths, lumber shopping list with your local prices & 1-page job sheet PDF.

Marking points along the top edge

1 of 1

Code and comfort check

Common IRC limits and comfort rules, shown as hints. Your local code decides.

1:1 marking template

Full-size tiles with a grid, tile map, a print check square and alignment crosses in every corner: match the crosses on neighbouring pages, tape, lay on the board, trace. Free.

Paper

Build pack

Stair width

Max stringer spacing

Tread boards

Picking tread boards sets the tread thickness above, so the bottom drop matches the boards you buy.

—

Cut list for every stringer, tread and riser, the shopping list with your local board prices, code hints & marking sequence on one 1-page job sheet PDF.

Instant 7-day browser access on this device · 14-day refund policy.

For reference only. Construction must follow your local code and a qualified professional. This tool does not size lumber for loads or certify a stair.

What to enter, and what you get

Use this tool to plan the geometry of a straight, cut wood stair stringer for a deck, a patio step-down or a floor-to-floor stair. Enter measurements directly; there is no PDF, photo, CAD or spreadsheet import.

Measurements and formats: Select inches or millimeters first. Enter whole numbers, decimals such as 36.5, or fractions such as 36 1/2. Values use the selected unit; enter inches rather than feet-and-inches notation.
Rise and run: Enter the finished landing-to-floor rise, then either the available horizontal run or a whole number of treads. In tread-count mode, each tread uses 10 1/2 in in inch mode or 267 mm in metric mode.
Construction choices: Set tread thickness, riser-board thickness (0 for open risers), nosing and whether the deck is the top step or the top tread sits flush. Choose 2x10, 2x12, 2x14 or an actual custom board depth.
Free results and downloads: Get riser and tread dimensions, pitch, throat, bottom-riser cut and stringer cut length; a marked board drawing, side view, 3D preview and copyable marking points. Download the 1:1 marking template as a tiled PDF on US Letter or A4.
Paid build pack: The $4.99 build pack adds width-based stringer count and spacing, cut and shopping lists, tread rip widths, stringer positions, a lumber cutting plan and a job-sheet PDF. One payment unlocks unlimited build-pack downloads in this browser for 24 hours; no subscription. Applicable tax is calculated at checkout.
Scope of the result: The tool calculates straight-flight layout geometry. It does not design winders, spiral stairs or load-bearing connections, size lumber for loads, or certify code compliance. The code and comfort checks are hints; use local requirements and qualified advice for construction.

A reproducible output example

Enter a 36 in rise and 48 in total run, select “Deck is top step,” and use 2x12 lumber (11 1/4 in actual depth), 1 in treads, 3/4 in riser boards and 1 in nosing. The current calculator returns:

Result	Calculated value
Risers	5 × 7.20 in
Treads	4 × 12.00 in
Stringer pitch	31.0°
Throat	5.08 in
Bottom-riser cut after subtracting tread thickness	6.20 in
Finished stringer cut length	59.17 in

These are calculated values, not measurements of a completed stair. The tool also shows inch readings rounded to the nearest 1/16 in. Open this example, see the formulas, or inspect the build-pack cut-list and shopping-list sample. Before using a printed template, print at 100% / Actual size and measure its check square.

What each number means

Riser height: The height of each step. Set it on the tongue of the framing square.
Tread depth: The run of each step, set on the body of the square. Nosing is added on top of this.
Pitch: The angle of the stringer: one riser over one tread. 30–37° feels right to most people.
Throat: Solid wood left under the deepest notch. Aim for 5 in or more on deck stairs.
Bottom drop: How much shorter the first riser is cut so the bottom step matches the rest once treads go on.
Cut length: Length of the finished stringer along the board, toe to top plumb cut. Buy the next standard length up.

Layouts for common heights

All worked examples

30 in deck 4 risers of 7 1/2″, 3 treads of 10 1/2″, 35.5° pitch, cut from a 6 ft 2x12. 36 in deck 5 risers of 7 3/16″, 4 treads of 10 1/2″, 34.4° pitch, cut from a 6 ft 2x12. 48 in deck 7 risers of 6 7/8″, 6 treads of 10 1/2″, 33.1° pitch, cut from a 8 ft 2x12. 60 in deck 8 risers of 7 1/2″, 7 treads of 10 1/2″, 35.5° pitch, cut from a 10 ft 2x12.

From measurement to cut stringer

Measure the rise on site. Set the landing pad first, then measure from it to the top of the finished deck. Measure at the spot the stairs will land, not at the deck post.
Lay it out here. Pick the run or the number of treads and your lumber. Check the code and comfort hints.
Mark one stringer. Follow the steps with a framing square and stair gauges, or trace the 1:1 template.
Test-fit, then copy it. Cut the first stringer, hold it in place, and use it as the pattern for the rest.

Read the illustrated how-to, see the formulas behind every number, or look up any height in the rise and run table.

Questions

How many steps do I need for my deck?

Divide the total rise by 7 1/2 in and round up: that is the number of risers. You get one tread fewer than risers because the deck itself is the top step. A 36 in deck needs 5 risers of 7 3/16 in and 4 treads.

Why is the stringer pitch not total rise divided by total run?

The stringer follows the steps, so its angle is set by one riser over one tread. The bottom tread is dropped by its own thickness and the deck forms the top step, so the line from the landing to the deck edge is steeper than the stringer itself.

What is the throat and how much do I need?

The throat is the solid wood left between the deepest notch and the bottom edge of the stringer. The American Wood Council deck guide (DCA 6) asks for at least 5 in on deck stairs, which is why 2x12s are the usual stringer stock.

What does "drop the stringer" mean?

The first riser is cut shorter by the thickness of one tread. Every other riser gets a tread on top and one below, the first only gets one on top, so without the drop the bottom step would be taller than the rest.

Is the 1:1 template really full size?

Yes. Print it at 100% ("Actual size") and measure the 1 in check square on the first page before you tape the tiles together. Each tile carries a 1 in grid so you can line them up exactly.

What is in the build pack?

A one-page job sheet for the whole stair: how many stringers for your width, a cut list for every stringer, tread and riser, a shopping list with estimated cost, code hints and the marking sequence. It unlocks for 7 days for $4.99 (was $9.99 · Early Launch Price · Save 50%).