9/16 Inch to MM
Fractional inch to millimeters
9/16 inch (9/16″)
14.2875 mm
= 1.4287 cm · 1 inch = 25.4 mm exactly
💡 Commonly used for hex bolt sizes.
Nearby fractional inches
| Fraction | mm | cm |
|---|---|---|
| 7/16″ | 11.1125 mm | 1.1112 cm |
| 1/2″ | 12.7 mm | 1.27 cm |
| 9/16″ | 14.2875 mm | 1.4287 cm |
| 5/8″ | 15.875 mm | 1.5875 cm |
| 11/16″ | 17.4625 mm | 1.7462 cm |
Also written as
9/16 to mm · 9/16 in mm · 9/16" in mm · 9/16 inch in mm · 9/16 inches to millimeters · 9/16 en mm · 0.5625 inch to mm
All of these mean the same measurement. The double-prime mark (″) and the plain quote (") both stand for inches, and en mm is simply the French and Spanish wording of the same question.
Closest metric drill size
14 mm
9/16″ = 14.2875 mm · difference 0.2875 mm
Metric drills step in 0.5 mm, so a fractional inch size rarely lands exactly on one. A 0.2875 mm gap is usually invisible in a clearance hole but changes the fit on a press fit or a tapped hole.
FAQ
How many mm is 9/16 inch?
9/16 inch equals 14.2875 mm. Since one inch is defined as exactly 25.4 mm, the result is 25.4 × 9 ÷ 16.
Why is the value exact?
The international yard and pound agreement of 1959 fixed the inch at exactly 25.4 mm, so fractional inch conversions terminate rather than repeat.