generated: '2026-07-19'
method: searched
source: https://docs.sequence.xyz + OpenAPI servers[]
summary: >-
  Sequence provides a sandbox by way of EVM testnets rather than a separate mock API. A single
  project access key (created in Sequence Builder at sequence.build) works against both testnet and
  mainnet; the developer selects the network by choosing the per-chain service host. Testnet
  transactions, gas, and NFTs carry no real value, and the Sequence testnet relayers sponsor gas so
  wallets can transact without funding.
separation:
  model: network-selection (per-chain host), not test-vs-live key prefixes
  access_key: X-Access-Key project access key issued in Sequence Builder; same key across networks
testnet_hosts:
  indexer:
    - https://sepolia-indexer.sequence.app
    - https://arbitrum-sepolia-indexer.sequence.app
    - https://base-sepolia-indexer.sequence.app
    - https://amoy-indexer.sequence.app
  relayer:
    - https://sepolia-relayer.sequence.app
    - https://arbitrum-sepolia-relayer.sequence.app
    - https://base-sepolia-relayer.sequence.app
    - https://amoy-relayer.sequence.app
  marketplace:
    - https://marketplace-api.sequence.app/sepolia/
    - https://marketplace-api.sequence.app/arbitrum-sepolia/
    - https://marketplace-api.sequence.app/base-sepolia/
supported_testnets:
  - sepolia (Ethereum)
  - arbitrum-sepolia
  - base-sepolia
  - amoy (Polygon)
  - optimism-sepolia
  - avalanche-testnet
  - bsc-testnet
gas_sponsorship:
  note: >-
    Testnet transactions can be sponsored via the Sequence Gas Tank / relayer so developers do not
    need testnet funds; mainnet sponsorship is configured per project.
notes:
  - No published static test tokens/cards; testing is performed against live testnet chains.
  - Get a project access key and testnet configuration from https://sequence.build