What does this round actually cost you? Enter the term-sheet numbers and see the real math — including the option-pool carve-out that quietly lowers your effective pre-money.
Most priced seed and Series A rounds sell 15-25% of the company to new investors. Add a 10% option-pool top-up carved out pre-money and existing holders typically end a round owning 25-35% less of the company, relatively, than they did before it.
In the standard structure the new pool is created before the investment closes, so it comes entirely out of existing holders' ownership. The investor's percentage is computed on the post-money and is unaffected by the pool — which effectively lowers the true pre-money valuation.
Multiply your current stake by (1 − investor share − new pool share). Example: you own 60%, the round sells 20% and adds a 10% pool — you now own 60% × 70% = 42%.
Related: pre-money valuation, option pool, SAFE conversion calculator