{"uid":"cap_PhhKKhvThG0fcDnEPhjg-","slug":"base-mainnet-erc-20-token-balance-lookup-88860933","name":"Base Mainnet ERC-20 Token Balance Lookup","description":"ERC-20 token balance of a Base mainnet address, incl. symbol, decimals, balance_formatted.","url":"https://x402-data-api.sigrunner.workers.dev/chain/token-balance","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","properties":{"token":{"type":"string","description":"0x-prefixed 20-byte ERC-20 contract address"},"address":{"type":"string","description":"0x-prefixed 20-byte holder address"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"chain":"base","token":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","symbol":"USDC","address":"0x4200000000000000000000000000000000000006","decimals":6,"balance_raw":"1050000","balance_formatted":1.05}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_HnZHRknqFiYBz1VRLnQLw","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the ERC-20 token balance for a given holder address on Base mainnet, including token symbol, decimals, and human-readable formatted balance.","exampleAgentPrompt":"What's the USDC balance (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) for wallet 0x742d35Cc6634C0532925a3b8D4C9b3C7e8Cb5f3 on Base mainnet, and show me the formatted amount with symbol?","exampleUseCases":null,"resultDescription":"A JSON object containing the raw token balance, a human-readable formatted balance (adjusted for decimals), the token symbol, and the number of decimals for the ERC-20 contract on Base mainnet.","failureModes":["Invalid or non-0x-prefixed contract address returns an error or empty response","Non-existent ERC-20 contract address (EOA or zero balance contract) may return zero or an error","Invalid holder address format causes a 400-level error","Address with no holdings returns balance of 0","Network or RPC issues on Base mainnet may cause timeouts","Payment not included or insufficient results in 402 Payment Required"],"whenToPreferThis":"Use this endpoint when you need the ERC-20 token balance (not ETH) of a specific wallet on Base mainnet, especially when you also need human-readable formatting with symbol and decimals. Prefer this over the ETH balance endpoint when querying ERC-20 tokens specifically. Use the wallet bundle endpoint if you need ETH balance alongside other wallet data in one call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-16T00:36:49.722Z","isFirstParty":false}