Ionic push notification for android keeps giving me error GCM_INVALID_AUTH

I was able to make push notification works on both android and ios for one of my mobile app.

Now, I’m trying to create another mobile app, however any push notifications keep giving me GCM_INVALID_AUTH.

I followed the following guides and I even tried to create a new app from scratch, just to test the notification.

I believe I setup everything correctly (SENDER_ID with Google project number, API Key for the ionic profile).

Google updated the web interface for creating the API key at some points because I could make everything work for my previous app even though I just started using the push notification. I’m getting very frustrated because I feel that this is a very straight forward step following the guide. I even tried it multiple times without any success.

Any advice?

Thank you very much.

Hello! I am having the same problems. Getting GCM_INVALID_AUTH as the error from PostMan.
Inside of ‘About this API’ for the Google Cloud Messaging it says that it is now Firebase Cloud Messaging (FCM) instead of GCM. Could this be the issue? Does ionic support FCM? Is there any way to get the old GCM on Google Cloud Platform?

‘Firebase Cloud Messaging (FCM) ( is the new version of GCM. If you are integrating messaging in a new app, start with FCM. GCM users are strongly recommended to upgrade to FCM in order to benefit from new FCM features today and in the future. Note that FCM and GCM are not supported by Cloud Platform Support; please check out our support page at for related questions.’

Hey guys,

I too was struggling with this issue, and ended up creating a Firebase project ( instead of trying to use the GCM API.

Used the Firebase projects own Server Key and Sender ID credentials that you can find as per my screenshot:

As soon as I had done this, all worked great


That worked for me!

Inside dashboard I went to Settings, then made a new Security Profile & Credential entry, set the GCM API Key equal to the Firebase project Server Key. I then also updated my client apps $ionicCloudProvider push sender_id to the new Firebase project Sender ID.

Ionic Team needs to update their push tutorial!

Thanks @smokeycam

Thank you very much! I have spent days until now that I found this post. Thanks a lot! It works now.

Sir, thank you very much for your reply. I really appreciate it. I thought I was going insane after trying to follow the step over and over again without any success.

They should just redirect users to FCM for any new API Server Key.

so many thanks, made my day , they have to update docs :unamused:

@smokeycam thanks for the solution.

Wow thanks I feel sooo much less crazy now. Posted the issue on their Github Ionic Cloud repo.