USDS, issued by the Sky Protocol smart contracts under the governance of SKY tokenholders, is an overcollateralized stablecoin that maintains a 1:1 peg with the U.S. dollar (USD) and is minted against crypto and real-world asset collateral held in protocol vaults [S1][S2].

Holders of USDS receive a token soft-pegged 1:1 to the U.S. dollar (USD), convertible 1:1 with USDC and DAI through the protocol peg module [S1][S3]. Yield accrues only when USDS is deposited into the Sky Savings Rate contract to receive sUSDS, an auto-compounding savings token whose exchange rate grows with real protocol revenue; the rate is variable and can fall to zero or negative [S4][S2]. The interface advertises zero entry and exit fees, though holders bear network gas fees [S4][S1].

There is no corporate token issuer; USDS is issued by permissionless, non-custodial smart contracts governed by SKY tokenholders [S1][S2]. The only named legal entity is interface operator Skybase International, governed under Cayman Islands law, which disclaims being a broker, dealer, exchange, investment adviser, custodian, or financial service provider [S5]. No regulator or license is claimed, and the regulatory framework is described as uncertain [S5][S2]. The documentation does not characterize USDS as a regulated instrument or fund interest [S2]. Eligibility excludes prohibited jurisdictions, OFAC-sanctioned persons, and certain U.S. residents; users self-custody and retain exclusive control of assets [S5][S2]. USDS is redeemable 1:1 to USDC and DAI [S1].

USDS is an ERC-20 token and sUSDS is an ERC-4626 yield vault token, issued on Ethereum as the primary issuance, liquidity, and governance home, with cross-chain transfers enabled via SkyLink to additional supported networks [S4][S3]. USDS is minted by depositing collateral into overcollateralized vaults or generated 1:1 against USDC and DAI, settling onchain on Ethereum subject to gas costs [S2][S3].

<Sources
  retrievedAt="2026-06-19"
  items={[
    { id: "S1", url: "https://sky.money/" },
    { id: "S2", url: "https://docs.sky.money/legal/skybase-international/user-risks.md" },
    { id: "S3", url: "https://docs.sky.money/legal/skybase-international/user-risks" },
    { id: "S4", url: "https://sky.money/susds" },
    { id: "S5", url: "https://docs.sky.money/legal/skybase-international/terms-of-use.md" },
  ]}
/>


# Active users (monthly) Methodology

## 1. Overview

Active users (Monthly) measures the number of unique addresses that engage in revenue-generating transactions with the USDS product suite on Sky. This metric captures user interactions with the protocol’s core accounting system, including the management of collateralized debt positions, borrowing, and repaying. It serves as a primary indicator of utility and adoption for the USDS asset within the decentralized finance ecosystem using a 30-day rolling window.

## 2. Data sources

- **Blockchain events**: `frob`, `grab`, and `fold` function calls from `Vat` contracts on Ethereum
- **External data**: Transaction metadata including sender addresses from the Ethereum blockchain

## 3. Step-by-step calculation

### Component A: Vault modification tracking

- **Purpose**: Identify active interactions with the USDS accounting system
- **Logic**: `frob`, `grab`, and `fold` function calls from `Vat` contracts are parsed to capture all modifications to vault states. Only successful transactions are included. Interactions are filtered to distinguish between standard vault operations and Peg Stability Module (PSM) activities based on collateral identification strings.
- **Key fields**: `collateral_id`, `transaction_hash`, `block_timestamp`

### Component B: User action categorization

- **Purpose**: Classify user interactions based on the type of vault activity
- **Logic**: Interactions are categorized by analyzing the change in debt and the change in collateral. Positive changes in debt classify an address as a Borrower, while negative changes classify an address as a Repayer. Similarly, positive changes in collateral classify an address as a Depositor, and negative changes classify an address as a Withdrawer. Specific interactions involving PSM collateral types are classified as trading activities.
- **Key fields**: `dart` (change in debt), `dink` (change in collateral)

### Component C: Address aggregation and deduplication

- **Purpose**: Calculate the final count of unique monthly users
- **Logic**: Transaction hashes identified in the vault modification stage are joined with blockchain transaction data to extract the unique `from_address` associated with each interaction. The resulting dataset is filtered to include only those associated with the USDS product. Unique addresses are then aggregated per 30-day window using a 30-day rolling UTC window to determine the number of active users (monthly).
- **Key fields**: `user_address`, `block_timestamp`, `product_id`

*This methodology was automatically generated by Token Terminal's methodology analyzer.*

Unique revenue-generating users over a rolling 30-day window.

Active users (monthly)

Stablecoins

Overcollateralized borrowers deposit funds into Sky and receive DAI stablecoin.

Sky is a non-custodial stablecoin protocol built on Ethereum. Sky (previously MakerDAO) was founded by Rune Christensen and launched in 2015.

SKY tokenholders own and govern the protocol. They currently take all of the total interest and PSM fees paid by borrowers (revenue). Sky’s investors include a16z, Polychain, IOSG Ventures, etc.

governance

github

twitter

discord

etherscan

website

Stablecoin issuers

Sky | Fees and revenues breakdown

USDS Stablecoin (USDS) is a U.S. dollar stablecoin issued by Sky.

Each token is redeemable one-for-one for U.S. dollars and is a direct claim on the issuer.

Retail investors and institutions can mint and redeem directly with Sky in USDC and DAI, and holders have a contractual right to redeem at par.

USDS has been issued on public blockchains since September 2024 and is native to Ethereum and Solana, with bridged versions on six more.

USDS StablecoinUSDS