> For the complete documentation index, see [llms.txt](https://docs.usd.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usd.ai/depositor/faq/usdai-and-susdai-101.md). # USDai & sUSDai 101 sUSDai is USD.AI's yield-bearing token, while USDai is its base stablecoin. Learn how they differ and how yield works. ### USDai and sUSDai
What is USDai and sUSDai? What’s the difference? **USDai** is the non-yielding base token of the USD.AI protocol. Each USDai is backed 1:1 by PYUSD at the protocol level and is designed for transfer, settlement, liquidity, and DeFi use. **sUSDai** is a separate ERC-4626 vault token received by staking USDai. Its exchange rate reflects the assets and economic rights held by the vault, including reserve or escrow assets and economic rights arising from qualifying GPU-backed loans, net of fees, losses, impairments, and recoveries. USDai holders do not receive GPU-loan yield merely by holding USDai. Solely by holding sUSDai, a holder does not directly own a particular GPU or borrower loan. For a deeper walkthrough, see the [sUSDai full guide](/depositor/susdai.md). * **USDai** = liquid, non-yielding, eligible for rewards * **sUSDai** = staked, yield-bearing, withdrawable after an unstaking period, eligible for rewards
Is USDai backed by GPU loans? No. USDai is backed 1:1 by PYUSD at the protocol level and does not itself provide a right to GPU-loan income or protocol revenues. Exposure to GPU-loan economics arises only through the separate sUSDai vault, which a holder accesses by staking USDai.
What does an sUSDai holder own? An sUSDai holder holds a pro rata vault position reflecting the vault's USDai holdings, reserve or escrow assets, and protocol-recognized economic rights arising from qualifying GPU-backed loans. A holder does not directly own a particular GPU, borrower SPV, borrower loan, Loan NFT, or Depositor NFT, and does not obtain a direct contractual claim against any particular borrower.
What are the Loan NFT and Depositor NFT? A Loan NFT is the protocol record associated with the borrower-side loan and collateral position. It is not the physical GPU collateral and does not replace the applicable loan and security documents. A Depositor NFT, referred to as a "Participation NFT" in certain operative loan documents, is the protocol record associated with the lender or vault-side economic right to receive payments under a qualifying loan. Depositor NFTs are held by or for the sUSDai vault and are not separately offered to sUSDai holders as individual loan participations.
What does the LoanRouterV2 do? LoanRouterV2 records loan-specific funding, payment schedules, repayment activity, outstanding balances, and distributions after a loan has been approved and documented. It does not independently select borrowers, determine creditworthiness, admit loans outside the applicable underwriting framework, or operate the sUSDai vault as a discretionary investment portfolio.
How does GPU-loan income reach the vault? Borrowers generate revenue through real-world GPU operations and make scheduled payments under their loan documents. Once payment funds enter the required protocol payment path, LoanRouterV2 and the applicable smart-contract and Depositor NFT mechanics record and route those payments. Received loan payments, reserve or escrow earnings, fees, losses, impairments, and recoveries are reflected in sUSDai's NAV and exchange rate under the applicable methodology.
How do I get USDai or sUSDai? Approved counterparties may access protocol-level USDai issuance and redemption under the applicable KYC, compliance, fee, and operational requirements. Other users may acquire USDai through supported secondary markets and application routes at . Timing, execution price, fees, slippage, and availability may depend on market liquidity, routing, bridge availability, and the relevant counterparties. Those application routes do not change USDai's underlying 1:1 PYUSD backing. sUSDai is obtained by staking USDai at the applicable exchange rate, at or buying directly via stables (contract will buy USDai and stake it for you) at .
What does it mean to redeem USDai? Approved counterparties may redeem USDai for PYUSD directly at the protocol level, subject to applicable KYC, compliance, fee, and operational requirements, at Other users may acquire, hold, transfer, or dispose of USDai through supported application routes and secondary markets. USDai should not be understood as directly and instantly redeemable by every holder at all times.
What does it mean to swap USDai? Swapping USDai means exchanging it for another token (e.g., USDC or USDT) via a liquidity pool on a DEX. This provides near-instant conversion, but the rate depends on current market conditions and pool liquidity.
What are the token contracts? * USDai: 0x0A1a1A107E45b7Ced86833863f482BC5f4ed82EF * sUSDai: 0x0B2b2B2076d95dda7817e785989fE353fe955ef9\ View View on browser: * [Arbitrum USDai](https://arbiscan.io/token/0x0A1a1A107E45b7Ced86833863f482BC5f4ed82EF) * [Plasma USDai](https://plasmascan.to/token/0x0A1a1A107E45b7Ced86833863f482BC5f4ed82EF?type=erc20\&chainid=9745) * [Base USDai](https://basescan.org/token/0x0A1a1A107E45b7Ced86833863f482BC5f4ed82EF) * [Arbitrum sUSDai](https://arbiscan.io/token/0x0B2b2B2076d95dda7817e785989fE353fe955ef9) * [Plasma sUSDai](https://plasmascan.to/token/0x0B2b2B2076d95dda7817e785989fE353fe955ef9?type=erc20\&chainid=9745) * [Base sUSDai](https://basescan.org/token/0x0B2b2B2076d95dda7817e785989fE353fe955ef9)
Where can I buy USDai/sUSDai? [app.usd.ai](https://app.usd.ai)
Where does USD.AI’s yield come from? USD.AI's yield comes from GPU backed loans and rewards associated with the stablecoins backing, which may include incentives passed to USD.AI by the issuer of the tokens backing USDai (e.g. PYUSD, itself backed by instruments including treasuries).
Who determines whether a loan qualifies? Qualifying GPU-backed loans must satisfy published standards relating to eligible hardware, loan-to-value limits, borrower equity, offtake characteristics, data-center requirements, collateral controls, insurance or collateral-warranty requirements, jurisdiction, monitoring, and compliance. Certain factors require documented secured-lender judgment. Any permitted exception must be documented and approved through the applicable credit and governance process.
What does GPU Finance do? GPU Finance Ltd. has historically acted, and continues to act on certain existing loans, as a rules-bound administrative and collateral agent, administering and enforcing predefined loan and collateral rights in accordance with the applicable loan documents. On more recent loans, GPU Finance holds sUSDai's participation interest as a lender of record in loans where sUSDai capital is deployed. As part of the lender group, and like other lenders, GPU Finance directs the applicable rules-bound administrative and collateral agent, such as GPU Servicer LLC, one of the service providers involved in loan servicing, to carry out those same functions, including verification of closing conditions, maintenance of collateral records, and enforcement of remedies following defined events of default. Neither GPU Finance nor GPU Servicer LLC manages sUSDai holder assets for discretionary return, determines ordinary-course yield allocation, selects individual users for redemption, or admits loans outside applicable protocol-approved criteria.
Are sUSDai returns guaranteed? No. Current APR is an annualized estimate based on income recognized by the vault during the stated historical measurement period. Expected APR is forward-looking and may rely on assumptions concerning anticipated loan deployment, borrower performance, reserve or escrow earnings, utilization, fees, promotional programs, and other estimates. Neither figure is guaranteed. Actual performance may be lower, zero, or negative.
What happens if a borrower misses a payment? If a borrower misses a payment, it enters a grace period during which it is charged default interest on the whole outstanding loan balance from the day after the missed payment. If the payment is still unpaid when the grace period ends, an Event of Default occurs and USD.AI records it onchain by calling liquidate on the loan. From then on, interest accrual on the loan pauses for NAV purposes; the borrower still owes it, at the default rate. The matter is then resolved through the offchain enforcement process. Once resolved, either the vault is made whole or the shortfall is recorded as an impairment. Any recovery above the loan’s frozen book value, up to the amount owed, increases NAV. Recovery cannot exceed the amount owed on the loan; any surplus goes back to the borrower.
*** ### Unstaking & Withdrawals
How do I unstake sUSDai? 1. Navigate to on the USD.AI app 2. Your request enters the redemption queue. 3. Redemptions are **automatically processed on fixed dates that occur every 30 days.** 4. When the window executes, go to **Pending Transactions** and click **Withdraw** to receive your USDai + accrued yield. Upcoming redemption dates are displayed in the app.
How long is the unstaking period? Redemptions are processed in **fixed windows every 30 days**, so your actual wait time will depend on when you submit your request relative to the next window.
Why is the unstaking period variable? USD.AI batches redemptions every 30 days. * If you unstake 1 day before the redemption window, your redemption will be available in 1 day. * If you unstake 15 days before the redemption window, your redemption will be available in 15 days. In all cases, redemptions are subject to redemption liquidity.
Is there a withdrawal queue? Where does instant liquidity come from? Yes, there is a defined redemption mechanism with:\ • A limited instant liquidity buffer (visible on-chain)\ • Additional redemptions handled via the protocol’s standard redemption flow The instant liquidity is pre-funded protocol liquidity.
How does USDai redemption actually work? For approved counterparties, protocol-level redemption is processed according to predefined on-chain rules once applicable conditions are met, including compliance requirements. For other holders, USDai is acquired or disposed of through supported secondary markets and application routes rather than direct protocol-level redemption. Those routes depend on market liquidity and the relevant counterparties.
Is QEV currently active? No. Redemptions currently use a 30-day FIFO queue, with requests processed sequentially at the applicable share price following the timelock and subject to available liquidity. The QEV is not active, and the associated contracts are to be audited before any transition away from FIFO.
Can governance choose who gets redeemed? No. No service provider or governance participant may select individual users for redemption or alter individual outcomes outside the applicable protocol rules. Any governance-approved changes to redemption parameters apply prospectively at the protocol level only and do not constitute discretionary intervention in submitted redemption requests.
How much USDai will I receive when I redeem sUSDai? The amount of USDai received upon redemption is based on the applicable redemption exchange rate and may be greater or less than the amount originally staked, depending on vault income, fees, losses, impairments, recoveries, and liquidity conditions.
--- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation by asking a question. Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters: ``` GET https://docs.usd.ai/depositor/faq/usdai-and-susdai-101.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.