{"uid":"cap_1Qhzw8Gyd_dWzlq-nh7Ta","slug":"ethereum-erc-20-balance-balanceof-32307ed8","name":"Ethereum ERC-20 Balance (balanceOf)","description":"ARYSPHERE sells AI-written verdicts on Base token contracts (a grade, a one-liner, a roast and the contract's facts) and Base/Ethereum chain reads, paid per call in USDC on Base over x402 v2. No account and no API key.","url":"https://api.arysphere.com/v1/ventures/x402_eth_reads_v1/eth_mainnet_erc20_balanceof?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","properties":{"token":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"ERC-20 contract, 0x + 40 hex"},"address":{"type":"string","pattern":"^0x[0-9a-fA-F]{40}$","description":"holder, 0x + 40 hex"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"ok":true,"chain":"ethereum","method":"balanceOf","result":"291368219","service":"x402_eth_reads_v1.eth_mainnet_erc20_balanceof"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_7XuJJnmQeAa1ftxSg_aPW","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the raw ERC-20 token balance of a holder address on Ethereum mainnet by calling the contract's balanceOf function.","exampleAgentPrompt":"What's the current ERC-20 token balance of wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 for the USDC contract at 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 on Ethereum mainnet?","exampleUseCases":[{"title":"DeFi portfolio balance snapshot","prompt":"Check how many tokens wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 holds of the USDT contract 0xdAC17F958D2ee523a2206206994597C13D831ec7 on Ethereum mainnet right now."},{"title":"Eligibility check for token-gated access","prompt":"Does the address 0xAb5801a7D398351b8bE11C439e05C5B3259aeC9B hold any tokens of the NFT-adjacent ERC-20 contract 0x1f9840a85d5aF5bf1D1762F925BDADdC4201F984 on Ethereum — return the raw balance so I can check if it's above zero."},{"title":"Pre-transfer balance verification","prompt":"Before I send a transaction, can you read the on-chain balanceOf for wallet 0x742d35Cc6634C0532925a3b844Bc454e4438f44e against the DAI contract 0x6B175474E89094C44Da98b954EedeAC495271d0F on Ethereum mainnet?"}],"resultDescription":"A JSON object with fields: ok (boolean success flag), chain (always 'base' or 'ethereum' identifier), method ('balanceOf'), result (the raw integer token balance as a string, in the token's smallest unit), and service (the internal service identifier). The raw balance must be divided by 10^decimals to get a human-readable amount.","failureModes":["Invalid contract address format (not 0x + 40 hex) returns a 400 error","Invalid holder address format returns a 400 error","Contract address is not a valid ERC-20 contract — call may revert or return 0","Payment not provided or insufficient — x402 payment required at $0.002 USDC","Ethereum mainnet RPC unavailable — service may return 5xx error","Address with zero balance returns result: '0' (not an error, but agents must handle this correctly"],"whenToPreferThis":"Use this endpoint when you need the live on-chain ERC-20 balanceOf value for any token/holder pair on Ethereum mainnet without running your own node. It is ideal for lightweight, single-address balance queries paid per-call via x402 micropayments. Prefer this over bundle endpoints when you need only the ERC-20 balance and want to minimize cost. Choose the ERC-20 Allowance sibling endpoint instead if you need to check how much a spender is permitted to spend on behalf of the holder.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-17T12:40:55.386Z","isFirstParty":false,"canonicalSlug":"ethereum-erc-20-balance-balanceof-32307ed8"}