number drill · nominal diameter

#17
drill bit size.

A #17 bit measures 0.1730 in across (4.394 mm).

The inch decimal is the published nominal designation; millimetres are a conversion.

Diameter conversion cross-checked

Calibrated relative diameter · 1 in reference

#17 · number

0.1730 in

4.394 mm

Designation#17number

Inch decimal0.1730nominal

Metric conversion4.394millimetres

Where this size sits from 0 to 1 inch

#17 · 4.394 mm on a zero to 25.4 millimetre scale. Neighbor marks: 4.4 mm, 11/64.

0 25.4 mm

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Measured neighbors

What sits beside #17.

“Nearest” means nominal diameter only. It does not make a neighboring size acceptable for a tolerance, tapping, reaming, or fastener application.

Other naming systemsABSOLUTE DIAMETER DELTA

4.4 mmmetric 0.1732 inΔ +0.006 mm 11/64fractional 0.1719 inΔ -0.029 mm 4.3 mmmetric 0.1693 inΔ -0.094 mm 4.5 mmmetric 0.1772 inΔ +0.106 mm

Same seriesNEAREST NOMINAL ROWS

#18number 4.305 mmΔ -0.089 mm #16number 4.496 mmΔ +0.102 mm

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

#17drill bit size.

What sits beside #17.

ASME.

#17
drill bit size.