You must use HTTPS and a supported browser (see below).
In addition, each payment method and browser has specific requirements:
Chrome
Chrome 61 or newer.
A saved payment cardarrow-up-right.
Chrome Mobile for Android
An activated Android Payarrow-up-right card or a saved cardarrow-up-right.
Note that when using Google Pay, including Android Pay, with a test mode keyarrow-up-right, you may see an "Unrecognized app" warning. This is expected and does not show up in live mode.
Microsoft Edge for Windows
Microsoft Edge 16.16299 or newer.
Last updated 7 years ago