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Tapping Drill Size Calculator

Developer Tools

Nominal minus pitch by material

Quick Answer

Tapping Drill Size Calculator: Nominal minus pitch by material. Tapping Drill Size Calculator uses standard developer formulas to compute accurate results instantly.

mm
mm
Tapping drill diameter8.5 mm

How it works

  1. 1Hole = 10 − 1.5 = 8.5 mm (ductile rule)
  2. 2Nearest standard drill: 8.5 mm (0.1 step, round up)
  3. 3Blind hole depth = thread depth + 0.7 × 10 (for the tap lead)

Coarse pitch reference (M×P): M3×0.5, M4×0.7, M5×0.8, M6×1.0, M8×1.25, M10×1.5, M12×1.75, M14/M16×2.0, M18/M20×2.5. Fine pitches follow the thread spec (e.g. M8×1, M10×1.25).

A hole too small overloads the tap (breaking it); too large leaves shallow threads. For stainless steel take the hole 0.05-0.1 mm larger and use spiral-point or spiral-flute taps with cutting fluid at low speed.

The theoretical minor diameter is d − 1.0825P; the empirical rules above aim for ~70% thread engagement, the strength/torque sweet spot. Verify finished threads with go/no-go gauges.

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How to Use

  1. Paste or type content: drop code/text into the Tapping Drill Size Calculator or fill the parameters.
  2. Choose mode/options: switch format, rules or processing as needed.
  3. Live output: results appear instantly — nothing is submitted, data stays in your browser.
  4. One-click copy: copy the output straight into your development environment.

Key Points

  • Tapping Drill Size Calculator is a free online developer tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: Nominal minus pitch by material.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Tapping Drill Size Calculator formula

Tapping Drill Size Calculator uses standard developer formulas to compute accurate results instantly.

FAQ

How do I use the Tapping Drill Size Calculator?
Open the page and fill in the input fields — results update automatically. Nominal minus pitch by material.
Are the results accurate?
Yes. Standard formulas and conversion factors are used and verified.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. Everything runs locally in your browser.

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Source & Updates

Based on RFC 4648, ECMA-262 and related specifications. Last updated: 2025-07

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Tapping Drill Size Calculator[EB/OL]. https://www.yijiansuan.com/en/c/dev/drill-size

Results provided by this tool are for reference only and do not constitute professional advice.