How can I verify a LinkedIn access token?

Additionally, you can filter the values:

https://api.linkedin.com/v1/people/~:(id,first-name,last-name,headline,picture-url,location,industry,current-share,num-connections,summary,specialties,positions)?format=json&oauth2_access_token={0}

You can use Token Introspection to get some informations about the token

https://learn.microsoft.com/en-us/linkedin/shared/authentication/token-introspection?context=linkedin/context

The url has been changed and the v1 API does not work anymore. Do use this one, if you need to verify access tokens generated from Linkedin.

https://api.linkedin.com/v2/me?oauth2_access_token=<your-token-here>

For other social media's, use can use urls from this gist: https://gist.github.com/pavittarx/15b46b08e779c2113864e9db399f35ac

I found that it can be done like this:

https://api.linkedin.com/v1/people/~?oauth2_access_token=YOUR-ACCESS-TOKEN

and that's it :).