Online Ruler in Inches (Fractional & Decimal)
Actual size on-screen inch ruler. True 1:1 physical calibration with 1/2", 1/4", 1/8", 1/16", and 1/32" fractional graduation lines.
Measurement Field
Place physical objects directly on screen, drag calipers, or tap rulers to drop guides.
How to Read Inch Ruler Fractions
Imperial rulers use a binary halving system where each subdivision halves the preceding length:
- 1 Inch: The tallest lines labeled with numerals (1, 2, 3...).
- 1/2 Inch: The second-tallest line halfway between whole inches.
- 1/4 Inch: Lines positioned halfway between the 1/2" and inch marks.
- 1/8 Inch: Medium-length ticks between the 1/4" lines.
- 1/16 & 1/32 Inch: Fine precision graduation ticks for high-accuracy carpentry and machining.
Fraction to Decimal & Millimeters
| Fraction | Decimal | Metric (mm) |
|---|---|---|
| 1/16" | 0.0625" | 1.588 mm |
| 1/8" | 0.1250" | 3.175 mm |
| 3/16" | 0.1875" | 4.763 mm |
| 1/4" | 0.2500" | 6.350 mm |
| 5/16" | 0.3125" | 7.938 mm |
| 3/8" | 0.3750" | 9.525 mm |
| 7/16" | 0.4375" | 11.113 mm |
| 1/2" | 0.5000" | 12.700 mm |
| 5/8" | 0.6250" | 15.875 mm |
| 3/4" | 0.7500" | 19.050 mm |
| 7/8" | 0.8750" | 22.225 mm |
| 1" | 1.0000" | 25.400 mm |
Inch Ruler FAQ
Technical details on screen PPI, calibration accuracy, and physical scale.
How do you read the fractional markings on this inch ruler?
Our actual size inch ruler divides each inch into binary fractions: the longest intermediate tick marks the 1/2" line, the next longest ticks mark 1/4" and 3/4", intermediate ticks mark 1/8" increments, and the smallest ticks represent 1/16" and 1/32" precision.
How many inches is an A4 or US Letter sheet of paper?
Standard US Letter paper measures 8.5 × 11.0 inches (215.9 × 279.4 mm). International Standard A4 paper measures 8.27 × 11.69 inches (210 × 297 mm).
Can I switch from decimal inches to fractional inches?
Yes! Our measurement readout automatically renders clean fractional representations (such as 3 5/16") when in normal view, and switches to 3-decimal precision (3.312") when measuring in high-precision mode.