TL;DR: A SAFE (simple agreement for future equity) is an instrument that lets a startup raise money in exchange for the right to equity in a future priced round. Unlike a convertible note, it is not debt: it generally carries no interest and no maturity date, which makes it simpler and faster for early-stage fundraising.
A SAFE is an agreement in which an investor provides capital now in return for shares later, when the company raises a priced equity round. Created by the startup accelerator Y Combinator, it was designed to simplify early fundraising by stripping out the debt features of a convertible note. There is typically no interest and no maturity date; the SAFE simply converts to equity when the triggering round occurs.
SAFEs usually include a valuation cap, a discount, or both, which reward the early investor for backing the company before a priced round set its value.
The key difference is that a SAFE is not a loan. A convertible note is debt, with interest accruing and a maturity date by which it must convert or be repaid. A SAFE has neither, so it carries less obligation for the founder and is generally quicker to execute. Both defer valuation and convert to equity at a future round, and both are early-stage equity instruments distinct from the growth debt used by revenue-generating companies.
Is a SAFE debt? No. Unlike a convertible note, a SAFE is not a loan and generally has no interest or maturity date. It is a right to future equity.
When does a SAFE convert? Typically at the company's next priced equity round, at a price adjusted by any valuation cap or discount in the agreement.
Related terms: Convertible Note · Pre-money / Post-money Valuation · Equity Dilution · Bridge Financing
