How to get SHA-1 key in Android Studio 2.3.1?

Try following this:How to get the SHA-1 fingerprint certificate in Android Studio for debug mode?.

1. Open Android Studio
2. Open your Project
3. Click on Gradle (From Right Side Panel, you will see Gradle Bar)
4. Click on Refresh (Click on Refresh from Gradle Bar, you will see List Gradle scripts of your Project)
5. Click on Your Project (Your Project Name form List (root))
6. Click on Tasks
7. Click on Android
8. Double Click on signingReport (You will get SHA1 and MD5 in Run Bar)
9. You can find it in the log of Gradle Console

Find signingReport from From Right Side Panel, you will see Gradle Bar

Double Click on signingReport

You can find it in the log of Gradle Console