number drill · nominal diameter

#2
drill bit size.

A #2 bit measures 0.2210 in across (5.613 mm).

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

Diameter conversion cross-checked

Calibrated relative diameter · 1 in reference

#2 · number

0.2210 in

5.613 mm

Designation#2number

Inch decimal0.2210nominal

Metric conversion5.613millimetres

Where this size sits from 0 to 1 inch

#2 · 5.613 mm on a zero to 25.4 millimetre scale. Neighbor marks: 5.6 mm, 7/32.

0 25.4 mm

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Measured neighbors

What sits beside #2.

“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

5.6 mmmetric 0.2205 inΔ -0.013 mm 7/32fractional 0.2188 inΔ -0.057 mm 5.7 mmmetric 0.2244 inΔ +0.087 mm 5.5 mmmetric 0.2165 inΔ -0.113 mm 5.8 mmmetric 0.2283 inΔ +0.187 mm

Same seriesNEAREST NOMINAL ROWS

#1number 5.791 mmΔ +0.178 mm #3number 5.410 mmΔ -0.203 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

#2drill bit size.

What sits beside #2.

ASME.

#2
drill bit size.