Calculate the correct drill bit size for your tapping operations. Supports various thread types and inch/metric measurements. Provides precise calculations for depth of thread and clearance.





248+ iOS apps curated and reviewed
If you already know Machinist Tap Drill Chart, this is the deeper bench. 248+ machinist tap drill chart apps for iPhone, all reviewed and ranked by user rating, recency, and download trend as of October 2026.
| # | App | Price | Rating | Ads | In-App Purchases | Updated | |
|---|---|---|---|---|---|---|---|
| 1 | Free | — | No | Yes | Aug 2026 | ||
| 2 | $0.99 | — | No | No | Aug 2026 | ||
| 3 | $1.99 | 4.3★ (30) | No | No | Aug 2026 | ||
| 4 | $0.99 | 4.5★ (22) | No | No | Aug 2026 | ||
| 5 | Free | 4.0★ (1) | No | Yes | Sep 2026 | ||
| 6 | Free | 4.7★ (12) | No | No | Oct 2026 | ||
| 7 | Free | — | No | Yes | Sep 2026 | ||
| 8 | Free | 5.0★ (2) | No | No | May 2026 |













Calculate the correct drill bit size for your tapping operations. Supports various thread types and inch/metric measurements. Provides precise calculations for depth of thread and clearance.