Inch Ruler: Actual Size Ruler in Inches Online
Inch ruler marked in 1/16 inch steps. Calibrate once and measure real inches on your screen.
How to read an inch ruler
An inch is split into 16 equal parts on this ruler. The line length tells you which fraction you are on:
| Line | Fraction | Decimal | mm |
|---|---|---|---|
| Longest, numbered | 1 inch | 1.0 | 25.40 |
| Long | 1/2 | 0.5 | 12.70 |
| Medium | 1/4 | 0.25 | 6.35 |
| Short | 1/8 | 0.125 | 3.18 |
| Shortest | 1/16 | 0.0625 | 1.59 |
Example: the object ends 3 short lines after the 2 inch mark. Each short line is 1/16, so the length is 2 and 3/16 inches. The guide readout shows fractions for you: tap the ruler edge at both ends of the object and the distance label appears. More detail: how to read a ruler.
Get an accurate inch measurement
- Set browser zoom to 100%.
- Press Calibrate and match the dashed card outline to a real bank card (3.370 x 2.125 inches).
- Hold the object flat with one end on 0 and read the other end.
If you do not have a card, pick your device in the Device tab or type your screen diagonal. Our screen size calculator tells you how many pixels make one inch on your display.
Inch fractions to millimeters
| Fraction | Decimal inch | mm |
|---|---|---|
| 1/16 | 0.0625 | 1.59 |
| 1/8 | 0.125 | 3.18 |
| 3/16 | 0.1875 | 4.76 |
| 1/4 | 0.25 | 6.35 |
| 3/8 | 0.375 | 9.53 |
| 1/2 | 0.5 | 12.70 |
| 5/8 | 0.625 | 15.88 |
| 3/4 | 0.75 | 19.05 |
| 7/8 | 0.875 | 22.23 |
Prefer metric? Open the cm ruler.
Frequently asked questions
How do I read the inch ruler?
Each numbered long line is a whole inch. The next longest line is 1/2 inch, then 1/4, 1/8 and the shortest lines are 1/16 inch. Count the small lines after the last whole inch to get the fraction.
Is this inch ruler actual size?
Yes, after you calibrate it once with a bank card or your device model. Until then the status line says Estimated.
How many inches can I measure on my phone?
A typical phone gives about 5 to 6 inches on the long edge. Press the menu button and choose Vertical, or go fullscreen, for the longest ruler.
How do I convert inches to centimeters?
Multiply inches by 2.54. For example 3 inches is 7.62 cm. You can switch the ruler to cm at any time.
Can I get a 6 inch or 12 inch ruler on screen?
A 6 inch ruler fits on most laptops and tablets. A 12 inch ruler needs a screen at least 12 inches wide, such as a 15.6 inch laptop or a desktop monitor in fullscreen.