How to compare color on two monitors side by side

Set up the screens before you judge anything. Open the tool in a window on the first monitor and create a session, which gives you a 4-character code. In a window on the second monitor, type that code or open the share link, and the same color appears right away. Next, set the same brightness on both monitors and turn off any automatic brightness or color changes. Give the screens a few minutes to settle, then sit where you can see both from the same distance and angle. Keep the room light the same for every look, or dim the room for both.

Start with the blue. Then type a gray such as #808080 into the HEX field, and after that a white such as #FFFFFF, and compare each one before you move on. Describe each gap in plain words, such as warmer, cooler, greener, duller or dimmer. A gray that looks warm on one screen and cool on the other is a tint gap. A white that looks dimmer on one monitor may be a brightness gap, so check that monitor's menu first. If the two match on all three colors, that's a good sign, though three colors don't cover every shade. If one screen's gray looks tinted, the tint page covers that in more detail.

The tool sends the same hue, saturation and lightness numbers to every screen, and each screen shows them through its own settings. Nothing in the tool measures what a screen produces, and it can't tell you which monitor is right. Each device needs an internet connection to stay in sync, and the session closes when the last device leaves. If you need numbers, a hardware colorimeter, also called a calibrator or spectrophotometer and used with its own software, is the way to measure a screen and calibrate it.