How to compare line by line the code?

I have in one file there are 2 functions looks very similar, but the differences are small and their eyes to see an extremely uncomfortable and long.
Is there any tool (preferably online) that you could enter the code 2 and see the distinct lines in them like on github for example when 2 file compare
June 14th 19 at 18:08
4 answers
June 14th 19 at 18:10
June 14th 19 at 18:12
June 14th 19 at 18:14
June 14th 19 at 18:16
araxis merge

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