NPT Tap Drill Chart
National Pipe Tapered Tap (NPT) Chart
| Tap Size | Drill Size | Tap and Drill Set |
| 1/16" NPT Tap | "C" Drill Bit | Only Sold Individually |
| 1/8" NPT Tap | "R" Drill Bit | 1/8" NPT Tap and Drill Set |
| 1/4" NPT Tap | 7/16" Drill Bit | 1/4" NPT Tap and Drill Set |
| 3/8" NPT Tap | 37/64" Drill Bit | 3/8" NPT Tap and Drill Set |
| 1/2" NPT Tap | 23/32" Drill Bit | 1/2" NPT Tap and Drill Set |
| 3/4" NPT Tap | 59/64" Drill Bit | 3/4" NPT Tap and Drill Set |
| 1" NPT Tap | 1-5/32" Drill Bit | 1" NPT Tap and Drill Set |
| 1-1/4" NPT Tap | 1-1/2" Drill Bit | Only Sold Individually |
| 1-1/2" NPT Tap | 1-47/64" Drill Bit | Only Sold Individually |
| 2" NPT Tap | 2-7/32" Drill Bit | Only Sold Individually |
| 2-1/2" NPT Tap | 2-5/8" Drill Bit | Only Sold Individually |
| 3" NPT Tap | 3-1/4" Drill Bit | Only Sold Individually |
| 3-1/2" NPT Tap | 3-3/4 Drill Bit | Only Sold Individually |
| 4" NPT Tap | 4-1/4 Drill Bit | Only Sold Individually |
Our most popular NPT Tap Sets:
5 Piece Carbon Steel NPT Pipe Tap Set, 1/8", 1/4", 3/8", 1/2" and 3/4" in Plastic Pouch Case
6 Piece Carbon Steel NPT Pipe Tap Set, 1/8", 1/4", 3/8", 1/2", 3/4" and 1" in Wooden Case
3 Piece Carbon Steel NPT Pipe Tap Set, 1", 1-1/4" and 1-1/2" in Plastic Pouch Case
6 Piece Carbon Steel NPT Pipe Tap Set 1/4", 3/8", 1/2", 3/4", 1" and 1-1/4" in Wooden Case