I've done about 4 startups now - and always chosen to split the equity evenly between the founders, despite the fact a tool like this one would have suggested I

I've done about 4 startups now - and always chosen to split the equity evenly between the founders, despite the fact a tool like this one would have suggested I would have been 'worth' more than parity. What this tool forgets is that a startup is a tough emotional journey and an emotional roller-coaster. In every startup's life there are moments of dispair, moments when it will all seem like too much effort. The ability to come through these as a team is as, or arguably more, important as being a brilliant coder, or someone having great contacts. In order to get that team spirit and togetherness that is key to the company being successful, I think it is better to split the equity more evenly. Or - to put it another way - in most cases, founders shares end up being worth almost nothing (statistically most startups never get a proper exit). It's far more important to look at what will increase the chance of that exit, rather than how much you will own at exit.