Why Across

Why Across is the fastest, cheapest, and most secure crosschain interoperability protocol.

This page is being expanded with detailed comparisons and benchmarks. Key points are outlined below.

Speed

Across delivers sub-2-second fills on mainnet through a competitive relayer network. Relayers front capital on the destination chain, so users don't wait for finality or message passing.

Cost

Across's aggregated settlement model (O(1) cost per bundle, not per fill) keeps fees low. The protocol batches all fills into a single settlement bundle every ~1.5 hours, amortizing gas costs across all users.

Security

Across has had zero security exploits since launch. The 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

Settlement Innovation

Three distinct settlement mechanisms optimize for different transfer types:

MechanismBest ForKey Advantage
IntentsMost transfers~2 second fills via relayer competition
CCTP V2 / CCTPFastLarge USDC (up to $10M)No relayer capital needed, native USDC
OFTUSDT0 transfersNative mint-and-burn, no wrapped tokens

Chain Coverage

23+ mainnet chains and 8 testnet chains, including first-mover support for:

  • Solana
  • MegaETH
  • Plasma
  • Monad
  • Hyperliquid (HyperCore + HyperEVM)

Integration Simplicity

One API call to bridge across any supported chain. The Swap API handles:

  • Mechanism selection (intents vs CCTP vs OFT)
  • Token routing and swaps
  • Gas estimation
  • Approval transaction generation

No need to understand the underlying settlement — just call /swap/approval and execute the returned calldata.

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