To ensure accurate on-screen ruler measurements, calibrate your display using a common object.

Use one of the following:

• Credit card
• US $1 bill
• A4 paper
• Letter-size paper

How to calibrate:

1. Place the object against your screen.
2. Adjust the PPI (Pixels Per Inch) using the input box or the + / – buttons in the top-right corner.
3. Match the on-screen size to the real-world size.
4. Once matched, your ruler will display precise measurements.

Once matched, your ruler will display precise measurements.