Pocket Hole Depth Calculator
Calculate Kreg jig pocket hole depth setting and screw length from workpiece thickness in inches.
What Is Pocket Hole Joinery?
Pocket hole joinery uses a stepped drill bit at a 15° angleto bore an angled pilot hole into one board, which is then screwed into a mating board using a self-tapping screw — no glue or traditional joinery required. It is the fastest way to build face frames, cabinet boxes, and furniture carcasses.
The Pocket Hole Depth Calculator provides the correct drill stop collar setting, jig height, and screw length for any material thickness. It is based on the Kreg Jig specification system and covers all standard material thicknesses from 1/2 in through 1-1/2 in, including thin sheet goods and thick solid stock.
Pocket Hole Depth Formula
The drill stop collar depth is set so the screw tip exits the angled hole approximately at the center of the mating board’s face. Given a 15° drill angle:
Drill Depth = T / sin(15°) − (screw tip offset)
T = material thickness (inches); sin(15°) ≈ 0.2588
Mathematical Form
D = T / 0.2588
D = drill stop depth from face (inches)
T = material thickness (inches)
0.2588 = sin(15°) — the drill angle constant
In practice, the Kreg Jig lookup table (below) incorporates this geometry plus a manufacturing offset so the screw exits precisely at the material centerline. The calculator above uses these pre-calculated values for Kreg-system accuracy.
Screw Length Selection
Screw length is selected so that the screw penetrates the mating board to a depth of at least T × 1.5 for sufficient holding power:
Screw Length ≈ (T × 1.5) + (T / sin(15°)) − full drill depth
Simplified: use the standard Kreg screw chart by thickness
Pocket Hole Settings by Material Thickness
Standard Kreg Jig drill stop collar settings, jig height settings, and recommended screw lengths by material thickness:
| Material Thickness | Stop Collar Depth | Jig Height Setting | Screw Length | Screw Thread |
|---|---|---|---|---|
| 1/2" (0.5") | 1-1/2" | A | 1" | Fine |
| 5/8" (0.625") | 1-1/2" | B | 1-1/4" | Fine |
| 3/4" (0.75") | 1-1/2" | C | 1-1/4" | Coarse or Fine |
| 7/8" (0.875") | 1-1/2" | D | 1-1/2" | Coarse or Fine |
| 1" (1.00") | 1-1/2" | E | 1-1/2" | Coarse |
| 1-1/4" | 1-1/2" | F | 2" | Coarse |
| 1-1/2" | 1-1/2" | G | 2-1/2" | Coarse |
Pocket Hole Screw Type Guide
| Screw Type | Thread | Best For | Drive Type |
|---|---|---|---|
| Coarse thread | Wide pitch | Softwood, pine, cedar, poplar | Square (Sq2) or Torx |
| Fine thread | Tight pitch | Hardwood, oak, maple, plywood, MDF | Square (Sq2) or Torx |
| HD (Heavy Duty) | Coarse wide | Structural framing, 1.5-in+ material | Square Sq2 |
| Coarse zinc | Wide pitch | Outdoor / treated lumber | Square Sq2 |
How to Set Up a Pocket Hole Jig
- Measure material thickness accurately with calipers — do not rely on nominal sizes. Actual 3/4 in plywood is often 23/32 in, which affects the stop collar setting.
- Set the jig heightby aligning the jig’s height guide line to the correct letter/number position on the jig body (A, B, C… correspond to material thicknesses — see table above).
- Set the drill stop collar on the stepped bit. For most Kreg systems, the stop collar is set to 1-1/2 in for material 1/2 in to 1-1/4 in thick. Slide the collar to the mark and tighten the set screw.
- Clamp the jig to the workpiece, flush with the face that will be hidden (the inner face of a drawer side, for example).
- Drill the pocket holes in each guide hole until the stop collar contacts the jig. Run the drill at high speed (1,500–2,500 RPM) with firm, steady pressure.
- Apply wood glue to the joint faces (optional but strongly recommended for structural joints). Align the pieces and clamp them flat.
- Drive the screw using a square-drive bit at medium torque. Do not over-drive — stop when the head is flush with the pocket bottom.