Online RulerStiffen a paper ruler
Fold a blank margin back along a crease that runs parallel to the ruler. Keep the printed scale flat and leave zero and every tick visible. A fold running along the length adds a firmer edge while keeping the marks on one flat face. Check the print before you fold.
- The printable page has a 10 cm test line for checking the print scale.
- The 15 cm and 6 in scales use separate physical print units on the same page.
- The ruler reads from the printed zero mark, even when a strip of paper extends past it.
- Print the page at Actual Size. Lay a physical ruler along the 10 cm test line and compare its endpoints. If they do not match, check for a print setting that resized the page and try again.
- Choose the scale you need and cut out a strip with a blank margin along its length. Leave paper beyond the first and last marks so you can handle the strip without covering them.
- Set the strip on a flat table. Use a straightedge to guide a crease in the blank margin, parallel to the printed scale. Fold that margin back and press the crease with your fingers.
- Lay the ruler down with the printed face up. Smooth any curl near the ends. Compare the folded strip with your physical ruler from zero to a visible tick before putting it to work.
Place the fold
Find a clear band of paper beside the scale. The crease should stay in that band from end to end. Hold a straightedge in place and lift the blank margin along its edge. If the paper starts to fold through the ticks, flatten it and move the guide farther into the margin. A crease across the strip can make the ruler bend where you need it to lie flat.
Read the printed face
Put the ruler alongside the object, with the printed face up and the ticks close to the edge you are reading. Line zero up with the start and look down from above at the far end. If the folded flap makes the strip rock, flatten the flap against the back and take the reading again. For marking a line, hold the paper in place as you make a pencil mark beside the tick.
Back a narrow strip
If you already cut away the blank margin, lay the strip flat on a piece of thin card. Attach the back with small pieces of tape while keeping the paper relaxed. Check the scale after mounting it. Trim the backing where it gets in the way, and leave enough room to see the full zero mark.
Can I fold both long margins?
Yes, if both are blank and the center stays flat. Make each crease parallel to the scale, then check that the ruler sits steadily on the table.
What if I cut off the test line?
Compare the finished strip directly with a physical ruler. Align the zero marks and check a tick near the far end.
Can I fold it across the middle for storage?
Store it flat when you can. If it already has a crosswise crease, flatten it and check the scale with a physical ruler before taking a reading.