Why Across
The fastest, cheapest, and most secure way to move assets across chains.
Integration Simplicity
One API call bridges or swaps across any supported chain. GET /swap/approval returns ready-to-execute calldata — Across handles routing, settlement, and gas under the hood, so your integration stays the same for every token, amount, and route.
Swap API Guide
Trade types, parameters, response shape, and a full integration example.
Swap API Reference
The complete GET /swap/approval parameter list and response schema.
Speed
Across delivers sub-2-second fills on mainnet — funds reach the recipient on the destination chain almost immediately, with no waiting on slow finality. The fastest way to feel it is to move something.
Cost
Across is one of the cheapest ways to move assets crosschain:
- Market-based pricing — every transfer is quoted competitively per route, not charged a flat bridge toll, so you get the lowest sustainable rate.
- Transparent, all-in fees — each quote returns an explicit
feesbreakdown, so the total cost is known before you submit. No hidden spread, no surprise surcharges. - Efficient infrastructure — low operating overhead is passed through to the fee you see, not tacked on top.
Security
Across's security model combines:
- Optimistic verification with UMA's Optimistic Oracle — bundles are accepted unless challenged
- Economic bonds — proposers stake capital that can be slashed for invalid bundles
- Only one honest actor needed — a single honest dispute is enough to reject a bad bundle
- V4 ZK proofs — Succinct/SP1 zero-knowledge proofs provide cryptographic settlement verification
Chain Coverage
23+ mainnet chains and 8 testnet chains, including first-mover support for Solana, MegaETH, Plasma, Monad, and Hyperliquid. Check whether a specific chain or token is supported:
Chain Checker
Check if Across supports your chain by ID or name.
Token Checker
Check if Across supports your token across all chains.