Welcome to UMA

UMA is a decentralized truth machine built around an optimistic oracle and a dispute-resolution system for bringing verifiable information onchain.

An optimistic oracle for verifiable onchain information.

UMA combines an Optimistic Oracle with decentralized dispute resolution. Applications can submit assertions or data requests, allow a challenge period, and escalate disputed outcomes to token-based voting.

1. Prediction markets and event resolution
2. Crosschain and interoperability workflows
3. Insurance and financial contracts
4. Custom assertions that need public evidence

Core Concepts

Optimistic Oracle V2Request, propose, dispute and settle data.

Optimistic Oracle V3Assertion-based verification for flexible applications.

Voting WalkthroughStake UMA, vote on disputes and manage rewards.

Choose the right documentation path

Start with protocol concepts if you are learning UMA, use the developer sections when integrating contracts, and use the voter guides when participating in DVM resolution.