number drill · nominal diameter
#43
drill bit size.
A #43 bit measures 0.0890 in across (2.261 mm).
The inch decimal is the published nominal designation; millimetres are a conversion.
Calibrated relative diameter · 1 in reference
#43 · number
0.0890 in
2.261 mm Designation#43number
Inch decimal0.0890nominal
Metric conversion2.261millimetres
Where this size sits from 0 to 1 inch #43 · 2.261 mm on a zero to 25.4 millimetre scale. Neighbor marks: 2.3 mm, 2.2 mm.
Measured neighbors
What sits beside #43.
“Nearest” means nominal diameter only. It does not make a neighboring size acceptable for a tolerance, tapping, reaming, or fastener application.
Source record
ASME.
The standard text is paywalled. Number and letter series are cross-checked against public manufacturer charts; exact standard edition/page verification remains a release gate.
Open source record