The discount is the simpler of the two conversion mechanics on SAFEs and convertible notes. At the next priced round, the holder converts at the round price reduced by the discount rate, typically 10 to 25%, with 20% the most common single number. When the instrument also carries a valuation cap, the investor converts at whichever price is lower: the discounted round price or the cap-implied price. The two terms are a floor and a ceiling on the same risk premium, and they never combine (no discount on top of the cap price).
The economic logic is compensation for early risk: the discount hands the early investor a better price than the round investors who waited for more evidence. Its weakness is symmetry. A 20% discount pays the same whether the priced round closes in 8 months or in 3 years, and whether the company’s value multiplied or merely survived. The cap exists precisely to repair that: it converts patience into ownership when the company outperforms.
In a term sheet negotiation the discount is rarely the battleground; caps carry the real economics. The founder’s discipline is simply to model both paths at signature: at what round price does the discount bind rather than the cap, and what does each scenario cost in fully diluted ownership.