[jrawlings]

I just did

return i.indexOf('.') > -1 ? i.substring(i.indexOf('.')+1) : false;

Seemed to pass all test cases

[EdgarVerona]

Aye, I did similarly, though for some reason I did >= 0 instead of > -1. I wonder what % of people choose one test approach vs. the other?

[taternuts]

I chose >= 0, it's fun to learn!