Co-founder Equity Calculator — Add the co-founders, set each person's equity percentage, and see the vesting schedule laid out month by month. Optionally add a future funding round to see how the cap table changes after a SAFE or priced round.
Your team and dilution numbers stay in your browser. Nothing is uploaded to a server.
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Co-founder Equity Calculatorとは？
Add the co-founders, set each person's equity percentage, and see the vesting schedule laid out month by month. Optionally add a future funding round to see how the cap table changes after a SAFE or priced round.
The default is standard startup vesting: 4 years total, 1-year cliff, monthly thereafter. Adjust if your team has a different arrangement.
使い方
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Add co-founders
Name and equity percent. The split must add up to 100% for the calculator to work.
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Set the vesting terms
Default: 4 years total, 1-year cliff, monthly. Adjust per founder if needed.
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Optionally add a funding round
Pre-money, raise, and (for SAFEs) cap. The dilution simulator estimates post-money ownership.
使用例
Two co-founders, 50/50 split
The classic equal split. Both vest 4 years with a 1-year cliff, so neither can leave with half the company after 3 months.
Founder A: 50%, Founder B: 50%
結果： Each founder vests 25% after year 1, then ~2% per month. Total vested at month 48: 100%.
Three-person team, weighted split
The technical co-founder gets more, the part-timer gets less, the business co-founder is in the middle. Adjust until the team agrees.
Tech: 45%, Biz: 35%, Part-time: 20%
結果： At a $5M pre-money, $1M raise, the cap table shifts: Tech 36%, Biz 28%, Part-time 16%, Investors 20%.
Simulating a SAFE round
You have $200K from a SAFE at a $5M cap. A year later, you raise a $2M priced round at $10M pre. See the founder dilution.
SAFE $200K @ $5M cap + Priced round $2M @ $10M pre
結果： SAFE converts at 4% of the cap table, priced round adds 20%, founders are diluted accordingly.
よくある質問
関連ガイド
How to Split Startup Equity Fairly (and Why 50/50 Is Usually Wrong)
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Last reviewed: 2026-09-25