The first time you register your device, you will be prompted to calibrate your device. The app will require you to do this once a week.

Before calibration make sure your measurement window is clean, and that there's not dust on the white surface of the calibration puck (underneath its protective cover). You may wipe the calibrator with a microfiber cloth to remove dust, but any solvent or fluid may damage the puck. Make every effort to keep the calibrator clean. Contact Purpl for a replacement when necessary. 

We advise to replace the calibration puck if it becomes dirty or skewed. Replacements can be purchased on the Purpl Web Store at An replacement white calibration puck can be found in the lower chamber on the foam below. 

To calibrate your device:

  • Remove the protective cover from the calibrator inside the case.
  • Place the white puck face down on the glass window of the device to calibrate. Be sure to twist off the black cap from the calibration module before calibrating or an "Please Remeasure White" error will be received. 
  • Press the "Calibrate Now" button from within the app.
  • The app will tell you whether Calibration was successful.
Don't forget to replace the Calibration Cover!
You're ready to measure!

If your device fails calibration, please fill out a support ticket at Typical failed calibration error is "Please Remeasure White" with Unhappy Face.