Error : Invalid key hash.The key hash does not match any stored key hashes

Invalid key hash. The key hash 8392849ZvfdjHakw2849H245738wue0 does not match any stored key hashes. Configure your app key hashes at http://developers.facebook.com/apps/ APP-ID

If you are getting the above error message while trying to log in to an App using Facebook App then the reason is that your key hash is not correct, just regenerate it and update it on the App's Developers console.

To get the Key Hash all you need to do is just need to copy the below code in onCreate() method of your launch Activity Class and watch the output in Android Studio LogCat,

try {
        PackageInfo info = getPackageManager().getPackageInfo(
                "com.your-package-name", 
                PackageManager.GET_SIGNATURES);
        for (Signature signature : info.signatures) {
            MessageDigest md = MessageDigest.getInstance("SHA");
            md.update(signature.toByteArray());
            Log.d("YourKeyHash :", Base64.encodeToString(md.digest(), Base64.DEFAULT));
            System.out.Println("YourKeyHash: ", Base64.encodeToString(md.digest(), Base64.DEFAULT));
            }
    } catch (NameNotFoundException e) {

    } catch (NoSuchAlgorithmException e) {

}

Note: Just replace com.your-package-name with your app package name in the above code.