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Vriksai Timber Intelligence

Dovetail Generator

Calculate dovetail tail count, miter angle, cheek, shoulder and spacing. Hardwood 1:8, Softwood 1:6, Plywood 1:7 ratios with cut list and canvas preview.

Why this calculation matters

Pin and tail layout decides both the strength and the look of a carcase corner. Too steep a slope breaks out the short grain during assembly.

Through DovetailHalf-BlindHardwood 1:8Softwood 1:6PDF Report
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Dovetail — Generator

Calculate dovetail tail count, miter angle, cheek, shoulder and spacing. Hardwood 1:8, Softwood 1:6, Plywood 1:7 ratios with cut list and canvas preview.

Setup
Board Dimensions & Layout
mm
mm
°
mm
mm
✓
Dovetail Layout Generated
—
tails
Number of Tails
—
pins
Number of Pins
—
°
Cutting Angle
—
mm
Tail Spacing
Spacing Layout from Left Edge
Dovetail Preview
Dimensions & Formula Trace
🔺 Dovetail Joint Generator
One of the strongest and most recognizable wood joints — used for 4000+ years. Interlocking wedge-shaped tails and pins create a mechanical lock ideal for box corners, drawers, cabinet carcasses and chests. The joint resists pulling apart by its wedge geometry alone.
Where Used?
Drawer BoxesBox CornersCabinet CarcassesBlanket ChestsJewellery Boxes
Formulas
Angle: theta = arctan(1 / ratio)Tail wide end: TW = T_narrow + 2 × thickness × tan(theta)N tails: round((W − min_pin) / (TW + min_pin))Spacing: S = (W − pin_width) / N_tails
About the Dovetail Generator
Dovetails are the mark of quality joinery — interlocking pins and tails that physically lock a corner together so it can't be pulled apart in one direction, which is exactly why they've held drawer fronts together for centuries. The angle and spacing are what make them work and look right: too steep and they can split, too shallow and they lose their grip. This generator lays out the pin and tail spacing for your board width and chosen angle, with sensible defaults for both softwoods and dense hardwoods like teak. The pins and tails layout comes out even every time, which beats working the dovetail spacing formula in pencil on the board edge.
Where Is This Used?
Drawer ConstructionFine FurnitureBoxes & ChestsHand-Cut JoineryCabinet Making
Sources & verification
  • Dovetail ratio geometry: θ = arctan(1/r) for 1:6, 1:7, 1:8
Formula checked against the sources above by an automated regression test (tests/verify-phase2.js) that derives each expected value independently of this page. Last reviewed .
FAQ
Best angle for Indian teak?
Teak and dense Indian hardwoods use 1:8 ratio (7.1°). Tight angle suits interlocked tropical grain and creates stronger mechanical lock. Softwoods like pine use 1:6 (9.5°) — wider angle compensates for softer grain.
Half-blind vs through dovetail?
Half-blind leaves a thin shoulder hiding the joint from the front — standard for quality drawer fronts. Through dovetail is fully visible from both faces — used for box corners and decorative joinery.
How many dovetails should I put on a drawer or box side?
There's no single right number — it's a balance of strength and looks. More, narrower pins and tails spread the glue surface and look refined (think fine jewellery boxes); fewer, wider ones are faster, stronger in some woods, and have a bolder, more rustic feel. A rough guide many makers use is to space tails roughly every 40–75 mm of board width, with a half-pin at each edge, then adjust so the spacing looks even. Let the height of the board and the style you're after lead the decision more than any fixed rule.
ResourcesView the formulasFormula Library
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Wood species data
Density, hardness and movement for 60 timbers
Browse all species 
How the calculation works
The slope is what makes the joint mechanical rather than adhesive: the tail is wider at the face than at its root, so it cannot pull straight out. That is also why the slope must suit the timber — too steep and the short grain at the pin tips breaks out on assembly.
Show the formula
Tail width at the wide face = narrow width + 2 x board thickness x tan(slope angle). Tail count N is derived from the board width and the minimum pin, spacing = (width - minimum pin) / N, and pins = N + 1.
Layout geometry only. 1:8 is the usual hardwood slope and 1:6 for softwood. Saw kerf, fit tolerance and wood movement after assembly are not included.
References
No external standard governs this calculation — it is arithmetic from your inputs. Take product-dependent figures from the manufacturer data sheet, not from here.
Limitations of this calculation
Generates layout geometry only. It does not account for stock thickness variation, saw kerf during cutting, wood movement after assembly, or the fit tolerance achievable by hand versus jig.
Do not use this for Jig setup without a test joint in scrap.
Figures are engineering estimates from the inputs and assumptions shown. Verify against the actual material and, where the result affects structure or safety, against a qualified professional.
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How to use this tool
  1. Enter your stock sizes below, then press Calculate.
  2. Pick your wood type / ratio from the dropdown.
  3. Fill in board width, board thickness, dovetail angle, min tail width. 
  4. Press Calculate. 
Worked example
With the tool's starting values — board width = 200, board thickness = 20, dovetail angle = 7.1, min tail width = 6, min pin width = 5 — pressing Calculate gives: 12 tails (number of tails); 13 pins (number of pins); 7.10 ° (cutting angle). 
Common mistakes to avoid