How most first money is raised now — fast, cheap, and much easier to get wrong than founders expect.
A SAFE (Simple Agreement for Future Equity) is an investor giving money now for shares later, when a priced round happens. No interest, no maturity date, not a loan.
A convertible note does the same thing but is legally a loan — it carries interest and a maturity date.
Both usually have a valuation cap (the maximum valuation at which they convert) and/or a discount (a percentage off the round price).
Because they let you raise quickly without agreeing a valuation, which is genuinely useful when the company is too early to value.
And because they are the single most common place founders are surprised. SAFEs are so easy to sign that founders stack four or five of them, then discover at the priced round that they have given away far more than they realised — because until conversion, none of it shows on the cap table.
You raise $500,000 on SAFEs with a $5M cap. Later you raise a $3M priced round at a $15M pre-money.
The SAFE holders do not convert at $15M. They convert at their $5M cap — so their $500k buys shares as though the company were worth $5M:
The cap gave them roughly three times the equity. That is exactly what it is for — they took the early risk.
The surprise is what it does to you. Before the round you believed you owned 100%. After conversion plus the new round, you are at roughly 68%, not the ~80% you might have assumed from the priced round alone.
Stack four SAFEs at different caps and this becomes genuinely hard to intuit. Model it before signing the next one.
The biggest: signing successive SAFEs without modelling cumulative conversion. Each one feels small. Together they are a round.
The second: not understanding post-money SAFEs. The current standard post-money SAFE fixes the investor's percentage — meaning all subsequent dilution before the priced round falls on you, not shared with them. This differs from the older pre-money version and it matters.
The third, for notes specifically: forgetting the maturity date is real. If no priced round happens before it, the note is technically repayable — which a startup usually cannot do. In practice it gets extended, but you are negotiating from a weak position.
Amount, cap, discount, date, and whether pre- or post-money. Founders lose track surprisingly fast.
Before signing a new one, calculate what happens if a priced round occurs at a realistic valuation. Sum all conversions.
With both, the investor gets whichever is better for them — not an average. Assume the more expensive outcome for you.
Post-money SAFEs fix the investor's percentage, so later dilution before the round lands entirely on the founders.
A common guideline is to keep total SAFE money under about 20–25% of the expected next round's post-money. Beyond that, do a priced round instead.
Standard YC SAFEs are well understood. A modified one is a different document, and the modifications are always in someone's favour.
For early rounds, angel money, and bridges between priced rounds — where speed and low legal cost genuinely matter.
Once the round is large, once there are many investors, or when investors want board seats and formal rights. At that point a priced round is cleaner and the extra legal cost is worth it.
This is educational information, not securities advice. Rules differ by country and change — get advice from a qualified professional in your jurisdiction before acting.
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