Thread Tap Drill Size & Depth Calculator
Find recommended drill bit diameters for cutting and roll-forming (fluteless) taps and calculate total drilling depth for blind holes according to DIN 336 / ISO standards.
Results
| Thread Major Dia D / Pitch P | — |
| Cut Tap Drill Size | — mm |
| Form (Roll) Tap Drill Size | — mm |
| Estimated Thread % | — % |
| Rec. Total Drill Depth | — mm |
| Drill Point Allowance | — mm |
Formulas
Cut Tap Drill: Dhole ≈ D - P
Form Tap Drill: Dform ≈ D - 0.5 × P
Blind Hole Depth: Ltotal = Lthread + Chip Clearance + 0.3 × Ddrill