Free Online Ruler
Display a calibrated millimetre or inch ruler on screen.
Online Ruler
Adjust until the purple reference line matches the 85.60 mm width of a standard bank card.
Enter a value to begin.
How to use this online ruler
- Adjust calibration until the reference line matches a physical bank card, then measure against the ruler.
- Check the inputs and preview, then use the primary action.
- Download, copy or use the result shown by the tool.
How the result is calculated
CSS pixels have a nominal 96-per-inch scale, so manual calibration is required for physical accuracy on each screen and zoom level.
All calculation and transformation work happens in this browser tab. No entered value is sent to an Noler Tools application server.
Important limitations
Results are provided for convenience and should be checked independently before an important decision. A format or checksum result never authenticates an identity, document, account, licence, vehicle or registration.
Frequently asked questions
Is this online ruler free?
Yes. It is free to use and does not require an account.
Does Noler Tools save my input?
No. The input and result remain in temporary browser memory and are not uploaded or saved by this site.