{"slug":"1gateway-dev-v1-onchain-base-balances-cd33dd","title":"Use when an agent needs what a Base address holds in one call instead of one RPC","host":"1gateway.dev","method":"GET","resource":"https://1gateway.dev/v1/onchain/base/balances","category":"market","description":"Use when an agent needs what a Base address holds in one call instead of one RPC call per token. Input: address; optional tokens (up to 20 ERC-20 addresses, comma-separated; default USDC, EURC, USDbC, WETH, cbBTC, cbETH, wstETH). Output: JSON block+time, ETH balance, per-token symbol, decimals, raw ","price_listed":0.002,"price_asked":0.002,"state":"answering","state_label":"Answering","checks_7d":1,"answered_7d":1,"latency_ms_median":30,"reported_calls_30d":2,"reported_payers_30d":2,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"address":"0x6246eee0355Dd7A93C888fE59e1151388A0cC5a1","tokens":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913,0x4200000000000000000000000000000000000006"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"additionalProperties":false,"properties":{"address":{"description":"Wallet or contract on Base mainnet (0x + 40 hex; mixed case must be a valid EIP-55 checksum). Bad input → 400 (not charged)","examples":["0x6246eee0355Dd7A93C888fE59e1151388A0cC5a1"],"pattern":"^0x[0-9a-fA-F]{40}$","type":"string"},"tokens":{"description":"Up to 20 comma-separated ERC-20 contract addresses on Base. Omit for the default set. A contract that is not an ERC-20 is listed with status not_an_erc20.","examples":["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913,0x4200000000000000000000000000000000000006"],"maxLength":900,"type":"string"}},"required":["address"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"address":{"type":"string"},"block":{"properties":{"number":{"type":"integer"},"timestamp":{"type":"string"}},"type":"object"},"chain":{"type":"string"},"chainId":{"type":"integer"},"codeSize":{"type":"integer"},"eth":{"properties":{"balance":{"type":"number"},"wei":{"type":"string"}},"type":"object"},"isContract":{"type":"boolean"},"nonZeroTokens":{"type":"integer"},"note":{"type":"string"},"rpc":{"properties":{"kind":{"type":"string"},"source":{"type":"string"}},"type":"object"},"tokenSet":{"type":"string"},"tokens":{"items":{"properties":{"address":{"type":"string"},"balance":{"type":["number","null"]},"decimals":{"type":["integer","null"]},"issuer":{"type":["string","null"]},"raw":{"type":["string","null"]},"status":{"type":"string"},"symbol":{"type":["string","null"]}},"type":"object"},"type":"array"},"transactionCount":{"type":"integer"}},"required":["chain","chainId","address","block","isContract","codeSize","transactionCount","eth","tokenSet","tokens","nonZeroTokens","rpc","note"],"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[{"day":"2026-10-18","reachable":true,"status":402,"valid_402":true,"asked_usdc":0.002,"price_match":true,"latency_ms":30,"error":null}],"description_full":"Use when an agent needs what a Base address holds in one call instead of one RPC call per token. Input: address; optional tokens (up to 20 ERC-20 addresses, comma-separated; default USDC, EURC, USDbC, WETH, cbBTC, cbETH, wstETH). Output: JSON block+time, ETH balance, per-token symbol, decimals, raw and decimal balance, nonce, isContract. Chain state only, no prices. Bad input: 400, not charged. Example: ?address=0x6246eee0355Dd7A93C888fE59e1151388A0cC5a1","last_updated":"2026-10-12T23:46:39.727Z","schemes":["exact"]}