The best solution for generating SHA1 key for android is from android studio.

[Click on Gradle on far right side][1]


[Click on refresh icon and you will see the name of the app][2]


[Click on the Tasks -> Report -> Signing Report][3]


[Find the SHA1 Key on bottom part in console][4]


 [1]: https://i.sstatic.net/eBPji.png
 [2]: https://i.sstatic.net/eCVpQ.png
 [3]: https://i.sstatic.net/2XrxZ.png
 [4]: https://i.sstatic.net/0U468.png

Thanks!!!!