Online RulerMeasure a Paper Strip’s Width
Lay the paper strip flat and measure straight across it, from one long edge to the other. Line up one edge with zero and read where the other edge meets the scale. Keep the strip square to the ruler so the reading gives the width across the paper.
- Width runs across the strip. Length runs along it.
- A diagonal reading spans more paper than a straight reading across parallel edges.
- The AR Ruler website and desktop extension offer a calibrated on-screen scale in centimeters or fractional inches.
- Flatten the strip on a smooth surface. If it curls, hold it down away from the spot you plan to measure.
- Turn the strip so its long edges cross the ruler at right angles. Pick a spot where both edges are easy to see.
- Put one long edge on the zero mark. On the AR Ruler screen scale, move the marker to the opposite long edge to read the width.
- Look straight down and read the tick where the opposite edge crosses the scale. Write down the width and unit together.
- If the cut looks uneven, repeat the reading at other points along the strip. Use the width at the spot where the paper needs to fit.
Use a Clear Edge
Check the edge for loose fibers, a folded corner, or a nick from the scissors. For a typical strip width, place the ruler across an intact part of the cut. If the strip has to pass through a slot, also check the widest part that will pass through it. A flared end can catch even when the middle fits. If you are comparing the strip to a marked cutting line, read the actual cut edge and keep the line as a separate reference.
Set Up the Screen Scale
Calibrate the on-screen ruler before using it for a physical measurement. AR Ruler saves the card calibration locally. It uses the card as a size reference and takes no data from it. Verify the scale after changing browser zoom or switching displays. The site invalidates the stored scale when it detects a relevant change. Set the strip close to the scale and view the edge head-on. If the display sits at an angle and the strip keeps sliding, use a ruler laid flat on a table.
Check a Printed Ruler
The AR Ruler printable sheet has a 15 cm scale, a 6 in scale, and a 10 cm test line. Print at actual size and check the test line against a physical ruler before measuring the strip. If the line comes out short or long, review the print settings and print again. Keep the sheet flat, especially near zero, so a lifted corner does not change how the paper edge lines up.
What if the strip tapers?
Record where you measured. For a strip that must fit along its full length, check the widest point. For a join, measure where the pieces will meet.
Can I start at a different tick?
Yes. If the zero end is worn, start at a clear tick. Subtract that starting reading from the reading at the opposite edge, using the same unit.
What if the edge falls between ticks?
Use the nearest marked division for a quick reading. If the edge is visibly between two marks, you can record that interval.