Millimeters to letter drill
Type a value in mm to get it in letter drill instantly.
Jletter drill
That's 1.07× as wide as the tap drill for 5/16-18 (F), while the tap drill for 3/8-16 (5/16") is 1.13× wider.
Convert the other way: letter drill to mm
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 mm to letter drill
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 mm = J letter drill.
Every unit
That drill in every system
Tables
mm to letter drill conversion table
| mm | letter drill |
|---|---|
| 6.15 mm | C letter drill |
| 6.35 mm | E letter drill |
| 6.63 mm | G letter drill |
| 7.04 mm | J letter drill |
| 8.03 mm | O letter drill |
| 9.09 mm | T letter drill |
| 9.35 mm | U letter drill |
| 10.3 mm | Y letter drill |
letter drill to mm conversion table
| letter drill | mm |
|---|---|
| A letter drill | 5.9436 mm |
| C letter drill | 6.1468 mm |
| E letter drill | 6.35 mm |
| G letter drill | 6.6294 mm |
| J letter drill | 7.0358 mm |
| O letter drill | 8.0264 mm |
| T letter drill | 9.0932 mm |
| U letter drill | 9.3472 mm |
| Y letter drill | 10.2616 mm |
Quick answers
Quick answers
- How many letter drill is 10 mm?
- 10 mm is X letter drill.
- How many letter drill is 7 mm?
- 7 mm is J letter drill.
The units
About these units
Millimeters (mm)
The diameter in millimeters, as metric drills are sold.
Letter drill (letter drill)
Letter drills A to Z.
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