5/16 inch is the short mark on a standard tape measure. It appears as a grey tick between each eighth-inch mark. The decimal equivalent is 0.3125 inches (7.94 mm).
On the Tape Measure
Count 5 marks of this size from the last full inch line to reach 5/16. On professional colour-coded tapes the grey marks are the shorter marks between the inch lines.
Conversion Reference
| Fraction | Decimal | Millimetres |
|---|---|---|
| 5/16″ | 0.3125″ | 7.94 mm |
| Half of 5/16 | 0.15625″ | 3.97 mm |
Common Woodworking Uses
Cabinet fitting, fine trim work, door hinge mortise depth. The 5/16 mark is common in: standard framing, finish carpentry trim fitting, and cabinet construction tolerances.
How to find it fast: On the TapeMath visual tape, hover over any mark to see its fraction, decimal, and mm immediately — no counting required.