aid: across
name: Across
description: Across is a crosschain interoperability protocol powering fast, low-cost token transfers and swaps across 20+ EVM chains and Solana. Built on an intents-based design with a permissionless relayer network and UMA optimistic oracle settlement, Across fills crosschain transfers in roughly two seconds with no custodial risk. Developers integrate a single unified Swap API (plus embedded crosschain actions, gasless flows, and deposit tracking) to move native USDC, USDT, ETH, and other assets between Ethereum, Arbitrum, Base, Optimism, Polygon, Solana, and more. The protocol has facilitated over $36 billion in volume for 5M+ users. Across is a Paradigm portfolio company in the crypto-infrastructure sector.
url: https://raw.githubusercontent.com/api-evangelist/across/refs/heads/main/apis.yml
accessModel:
  pricing: unknown
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  label: Self-serve signup
  confidence: medium
  source:
  - authentication
  generated: '2026-07-22'
  method: derived
image: https://across.to/logo.svg
x-type: company
x-source: vc-portfolio
x-backed-by:
- paradigm
x-tier: profiled
x-tier-reason: enriched-from-public-surface
specificationVersion: '0.20'
created: '2026-07-17'
modified: '2026-07-17'
tags:
- Company
- Crypto Infrastructure
- Cross Chain
- Bridge
- Interoperability
- Blockchain
- DeFi
- Web3
- Swap
- Payments
apis:
- name: Across Swap API
  description: The unified REST entry point for all crosschain operations on Across — request swap/bridge quotes and approval data, execute embedded crosschain actions on the destination chain, run gasless flows, enumerate supported chains/tokens/sources, and track deposit lifecycle status. Authentication is a Bearer API key plus a 2-byte hex integratorId query parameter; testnet requires no credentials.
  humanURL: https://docs.across.to/introduction/swap-api
  baseURL: https://app.across.to/api
  tags:
  - Cross Chain
  - Bridge
  - Swap
  - Payments
  properties:
  - type: Documentation
    url: https://docs.across.to
  - type: APIReference
    url: https://docs.across.to/api-reference
  - type: GettingStarted
    url: https://docs.across.to/introduction
  - type: Authentication
    url: authentication/across-authentication.yml
  - type: Conventions
    url: conventions/across-conventions.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: DomainSecurity
  url: security/across-domain-security.yml
- type: Website
  url: https://across.to
- type: Documentation
  url: https://docs.across.to
- type: APIReference
  url: https://docs.across.to/api-reference
- type: GettingStarted
  url: https://docs.across.to/introduction
- type: Blog
  url: https://across.to/blog
- type: GitHubOrganization
  url: https://github.com/across-protocol
- type: SignUp
  url: https://docs.across.to/introduction/api-keys
- type: MCPServer
  url: mcp/across-mcp.yml
- type: SDKs
  url: packages/across-packages.yml
- type: Packages
  url: packages/across-packages.yml
- type: LLMsTxt
  url: llms/across-llms.txt
- type: Authentication
  url: authentication/across-authentication.yml
- type: Conventions
  url: conventions/across-conventions.yml
- type: VulnerabilityDisclosure
  url: security/across-vulnerability-disclosure.yml
- type: Security
  url: security/across-vulnerability-disclosure.yml
- type: TrustCenter
  url: security/across-trust-center.yml
x-enrichment:
  date: '2026-07-19'
  status: backfilled
  pass: local-v1
  note: backfilled from .gitignore signal + verified work evidence