Turn each founder's contribution into a fair share of ownership — set a weight for every founder and see the split instantly.
Set how many founders you have, then weight each one's contribution. Nothing is stored.
There's no single right answer, but the fairest splits usually reflect what each founder actually brings to the table — not just an even slice for everyone. This tool lets you weight each founder's contribution and converts those weights into percentages that always add up to 100%.
When you set each founder's weight, think about:
A full-time founder who quit their job is contributing far more than a part-time advisor. The biggest equity usually goes to whoever is all-in and carries the most execution risk.
Original ideas matter, but execution matters more over the life of a company. Weight ongoing work and responsibility, not just who first had the spark.
Money invested, hard-to-replace skills, key customer relationships, and reputation all add value. Factor them in — but remember that ownership earned over years usually outweighs what's contributed on day one.
Sometimes an even split is right — especially when founders contribute equally and are all-in full time. But an automatic 50/50 can breed resentment if one person does far more. Weighting contributions, as this tool does, often leads to a more durable agreement.
Vesting means a founder earns their equity over time rather than owning it all immediately — commonly over 4 years with a 1-year cliff. It protects the company and the remaining founders if someone leaves early, and almost every serious startup uses it.
A cliff is a minimum period — usually one year — that a founder must stay before any equity vests at all. If they leave before the cliff, they walk away with nothing. After the cliff, equity typically vests gradually each month.
Yes. Verbal handshakes between founders are the source of countless disputes. A written founder agreement covering the split, vesting, roles, and what happens if someone leaves protects everyone and is far cheaper than fighting about it later.
This calculator provides a general, simplified estimate for educational purposes only. It is not legal or financial advice. No attorney-client relationship is formed by using this tool.
FirmLift Interactive Tool · Demonstration