How Frax Finance works
Strip away the product names and Frax comes down to one question that every stablecoin has to answer: why does this token stay worth a dollar? Frax's answer today is collateral you can redeem against, kept productive by a set of autonomous contracts. Here is how that fits together.
The peg: redemption, not faith
A stablecoin holds its value when the market believes it can always be exchanged for the thing it represents. Frax's dollar stablecoin is designed to be redeemable against collateral the protocol holds. If the token trades below a dollar, arbitragers buy it cheaply and redeem it for a dollar of value, which pushes the price back up. If it trades above a dollar, new supply can be created against collateral, which pushes the price back down. That two-way pressure is what keeps the peg tight.
This is the part that changed most over the years. Early FRAX leaned on an algorithm and the FXS token to hold the peg with less than full backing. After 2022, governance moved to full collateralization, so the dollar stablecoin is meant to be backed one-for-one. The exact composition of that backing is a live figure — check the documentation for the current breakdown.
AMOs: keeping reserves productive
Holding a pile of idle collateral would be safe but wasteful. Frax's answer is the Algorithmic Market Operations Controller, or AMO. An AMO is an autonomous smart contract with one strict rule: it can deploy the protocol's collateral into strategies — providing liquidity, lending it out, and so on — but only in ways that do not break the stablecoin's peg. If an action would weaken the peg, the AMO cannot take it.
The point of AMOs is to earn yield on reserves and deepen liquidity without handing discretion to a person. They are bounded by code, and the profit they generate is what ultimately flows to the governance token and to savers in the sFRAX vault.
Where the yield comes from
When you stake the dollar stablecoin into sFRAX, you are not being paid out of thin air. The vault distributes part of the protocol's real yield — interest from lending, returns from AMO strategies, and revenue tied to short-term rates. Because those inputs move, the rate moves too. Any APY you see quoted should be treated as a live figure.
How value reaches the token
Fees, redemption spreads and AMO profits accumulate at the protocol level. Historically that value accrues to FXS holders, particularly those who lock their tokens as veFXS for voting power. Under the North Star rebrand the same token is being renamed FRAX and given an additional job as the gas and staking token of the Fraxtal network, which ties usage of the chain back to the token. The token map and governance pages go deeper on this.
The one-sentence version
Collateral plus redeemability holds the peg; AMOs put that collateral to work within strict limits; and the yield and fees that result flow to savers and to the governance token.