Online RulerMove a screen ruler between monitors
Move AR Ruler all the way onto the monitor you plan to use, then check its scale against a bank card before measuring. A saved scale can give the wrong reading on a different screen. Keep the ruler window on that monitor until you finish.
- AR Ruler saves card calibration locally. The saved scale can carry over when you move the window.
- A detectable browser zoom or display change invalidates the stored scale. Check it yourself after a move, even if the ruler still shows a scale.
- The website, desktop ruler, and extension offer centimeters and fractional inches. Start at zero on the left and move the marker to the far edge.
- Move the whole window to the destination monitor. Set its final size and browser zoom before checking the ruler.
- Hold the long edge of a bank card against the card guide. The nominal long edge of an ISO ID-1 card is 85.60 mm. Match both ends to the guide.
- If the ends do not line up, redo the card calibration on that monitor and compare the guide with the card again.
- Choose your unit. Line up the first edge of the object with zero and move the marker to the far edge.
- Repeat the card check whenever you move the window to another screen or change the browser zoom or display settings.
Use one screen at a time
Keep the window clear of the gap between monitors. A ruler that crosses the gap gives you no continuous surface for lining up the object. Even monitors that look alike can show different physical spacing between ticks. If the object will fit on either display, pick the one you can reach comfortably. Check the card there before you set the object in place.
Check the full card edge
Line up one end of the card with the start of the guide and look straight at the other end. A gap there is easier to see when the card is flat and parallel to the guide. If the calibration is off, fix the scale first. The marker shows the distance from zero to its current position. The spacing between ticks stays the same.
Use paper for a flat surface
If the object is awkward to hold against an upright monitor, use the printable sheet. It has a 15 cm scale and a 6 in scale, each sized independently for print. Print at actual size and compare the 10 cm test line with a physical ruler before using the sheet. If the line differs, check the print scaling and try again.
Do I check again when I move back?
Yes. Compare the guide with the card on the original monitor before taking another reading.
What if I change zoom to fit the object?
Set the new zoom, check the guide against the card, and recalibrate if the ends differ. Then line up the item with zero.
Does the site read my card?
You match the card to the guide by sight. AR Ruler saves the scale locally and takes no data from the card.