Number drill to millimeters
Type a value in drill to get it in mm instantly.
5.105mm
That's about the same as the tap drill for 1/4-20 (#7).
Convert the other way: mm to drill
What it means
How wide is that hole?
Sizes from ASME B94.11M. Between two listed drills the label shows the nearest one; the millimeters are exact.
The math
How to convert drill to mm
Number and letter drills are a table: #29 = 0.1360 in = 3.454 mm, #7 = 0.2010 in, F = 0.2570 in. Millimeters = inches × 25.4.
Example: #7 drill = 5.1054 mm.
Every unit
That drill in every system
Tables
drill to mm conversion table
| drill | mm |
|---|---|
| #1 drill | 5.7912 mm |
| #3 drill | 5.4102 mm |
| #5 drill | 5.2197 mm |
| #7 drill | 5.1054 mm |
| #10 drill | 4.9149 mm |
| #15 drill | 4.572 mm |
| #20 drill | 4.0894 mm |
| #21 drill | 4.0386 mm |
| #25 drill | 3.7973 mm |
| #29 drill | 3.4544 mm |
| #30 drill | 3.2639 mm |
| #33 drill | 2.8702 mm |
| #36 drill | 2.7051 mm |
| #40 drill | 2.4892 mm |
| #43 drill | 2.2606 mm |
| #50 drill | 1.778 mm |
| #60 drill | 1.016 mm |
| #70 drill | 0.7112 mm |
| #80 drill | 0.3429 mm |
mm to drill conversion table
| mm | drill |
|---|---|
| 0.343 mm | #80 drill |
| 0.711 mm | #70 drill |
| 1.02 mm | #60 drill |
| 1.78 mm | #50 drill |
| 2.26 mm | #43 drill |
| 2.49 mm | #40 drill |
| 2.71 mm | #36 drill |
| 2.87 mm | #33 drill |
| 3.26 mm | #30 drill |
| 3.45 mm | #29 drill |
| 3.8 mm | #25 drill |
| 4.04 mm | #21 drill |
| 4.09 mm | #20 drill |
| 4.57 mm | #15 drill |
| 4.91 mm | #10 drill |
| 5.11 mm | #7 drill |
| 5.22 mm | #5 drill |
| 5.41 mm | #3 drill |
| 5.79 mm | #1 drill |
Quick answers
Quick answers
- How many mm is #1 drill?
- #1 drill is 5.7912 mm.
- How many mm is #10 drill?
- #10 drill is 4.9149 mm.
- How many mm is #7 drill?
- #7 drill is 5.1054 mm.
The units
About these units
Number drill (drill)
Number drills #1 to #80.
Millimeters (mm)
The diameter in millimeters, as metric drills are sold.
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