Modelling dilution
How the dilution calculator works and how to read its output.
Last updated August 3, 2026
What the calculator does
Enter your pre-money valuation, the amount raised, and any option pool expansion. The model returns post-money valuation, the new investor percentage, and the resulting founder position.
Pool shuffle
If the pool is created pre-money, existing shareholders absorb the dilution before the new money lands. The calculator shows both arrangements so you can see the difference before you negotiate it.
Compounding across rounds
Run several rounds in sequence to see how ownership compounds down. Founders are routinely surprised by the third round, not the first.
Limits
Every result is an illustrative model. It does not account for liquidation preferences, participation, anti-dilution adjustments, or side letters. It is educational output, not a valuation and not advice.
Was this article helpful?