Co-Founder Equity Split Calculator

Splitting equity is one of the hardest early conversations. Score each founder on the factors that actually build the company and get a fair, defensible starting point for the discussion.

50.0%
Idea & IP
5
Capital invested
5
Time & commitment
5
Risk taken
5
Skills & execution
5
50.0%
Idea & IP
5
Capital invested
5
Time & commitment
5
Risk taken
5
Skills & execution
5

Suggested split

50%
50%
Founder 150.0%
Founder 250.0%

A starting point for the conversation — not legal advice. Vest equity over 4 years with a 1-year cliff, and put the final split in writing with a lawyer.

How the equity split is calculated

Each founder is scored 0–10 on five contribution factors — idea & IP, capital invested, time & commitment, risk taken, and skills & execution. We total each founder's scores and convert them to a percentage of the whole. It's the same weighted-contribution approach behind popular equity calculators, made adjustable so you can weigh the factors your team cares about most.

Should co-founders split equity 50/50?

Equal splits are common and often the right call when both founders join at the same time with comparable commitment — it signals trust and avoids resentment. But an equal split isn't automatically fair: a founder who brings the idea, works full-time, and puts in capital is contributing more than one joining later part-time. Use this calculator to make those differences explicit, then decide together.

Protect the split with vesting

Whatever you agree, put it on a 4-year vesting schedule with a 1-year cliff so equity is earned over time, not handed over on day one — it protects everyone if a co-founder leaves early. This tool is a starting point, not legal advice; finalize the split with a lawyer. When you're ready to launch, plan spend with our runway calculator and list your startup on Launchory. Building tools for teams? Explore HR & hiring and SaaS startups already listed.