The most confused pair of words in fundraising, and the arithmetic that decides what you own afterwards.
Pre-money is the agreed value of the company before the new money arrives.
Post-money = pre-money + the amount raised.
Ownership is always calculated on post-money:
Investor % = Amount invested ÷ Post-money valuation
That one line resolves most first-round confusion.
Because '$5M valuation' means two different deals depending on which one is meant, and the difference is real money.
Raising $1M at $5M pre → post is $6M → investor owns 16.7%. Raising $1M at $5M post → investor owns 20%.
Same headline number, 3.3% of your company different. Always ask which.
You own 100%. You raise $1,000,000 at a $4,000,000 pre-money.
Your 80% of a $5M company is notionally worth $4M — the same as your 100% was worth before. You did not lose value; you exchanged 20% for $1M of cash and, hopefully, the growth it buys.
Now add an option pool. The investor asks for a 10% pool created pre-money. That pool comes out of the existing shareholders — you. So you end at roughly 70%, not 80%, and the investor still has 20%.
That is the 'option pool shuffle', it is standard, and it is negotiable. Knowing it exists is most of the battle.
First-time founders often optimise hard for the highest possible valuation. A valuation you cannot grow into makes the next round much harder — you must roughly triple the business to justify a higher price, and if you cannot, you face a down round, which is painful and can trigger anti-dilution provisions that hurt you badly.
A slightly lower valuation with a great investor and clean terms beats a high number with bad terms almost every time.
The second mistake: not asking whether the option pool is pre- or post-money. It is worth several percent of your company.
'Is that pre or post?' It is a normal, professional question and the answer changes your ownership.
Amount ÷ post-money. Do the arithmetic yourself before the meeting, not afterwards.
A pre-money pool dilutes only the existing shareholders. Ask, and negotiate — it is one of the most commonly conceded terms.
Today's decision compounds. Founders are routinely surprised at Series B by arithmetic that was fully visible at seed.
Liquidation preference, board composition and anti-dilution can matter more than valuation. Price is the number you brag about; terms are the number you live with.
The moment a number is mentioned, and before signing anything.
Do not agonise over valuation on a small SAFE from an angel who is helping you. The relationship and speed are worth more than a point of dilution at that size.
Apply this to your own startup in My Full Journey (free account).