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Ethereum Onchain Data

onchaincheck.dev

Re-check up to 5 tokens you hold or watch in one call, on Base, Ethereum, Arbitrum, Optimism, Polygon or Solana: each token's 0-100 risk score, level, reason codes, price, liquidity and a fingerprint. Send the fingerprints back as since to get what changed (new risks, owner or authority changes, liquidity or price moves of 10%+) and a short list of alerts. One price for the whole list, made for po

Category
Service
Networks
Base
Starting price
$0.001
Paid calls, 30 days
139

Paid endpoints

68 endpoints, sorted by usage. Prices are per request.

EndpointPriceNetworkCalls / 30d
GET/address/screen

Is this address sanctioned? Screens a crypto address against the US Treasury OFAC SDN list's published digital currency addresses (ETH, USDC, USDT, XBT, SOL, TRX and others): the listed entity, programs and listing date on a match, or not found as of the list date. Adds whether it is a wallet (EOA) or contract on Base, Ethereum, Arbitrum, Optimism or Polygon, or a wallet or program-derived address on Solana. Not legal advice.

$0.005Base4
GET/arbitrum/contract

Identify what lives at a Arbitrum One address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and ETH balance.

$0.005Base3
GET/x402/ping

The smallest real x402 paid call: costs $0.001 in USDC and returns ok with the server time and payment network. Useful for checking that an x402 client can sign and settle a payment end to end.

$0.001Base3
GET/arbitrum/allowance

ERC-20 allowance on Arbitrum One: how much a spender may transfer from an owner, whether the approval is effectively unlimited, the owner's balance, and the amount the spender could move right now.

$0.005Base2
GET/arbitrum/balances

Native ETH balance of a Arbitrum One wallet plus the balances of up to 20 ERC-20 tokens you list, formatted with each token's symbol and decimals, read live from Arbitrum One.

$0.005Base2
GET/arbitrum/gas

Current Arbitrum One gas conditions: block number, base fee, gas price and priority fee in gwei, and the estimated cost in ETH and USD of a native transfer and an ERC-20 transfer (Chainlink ETH/USD).

$0.005Base2
GET/arbitrum/new-pools

New trading pools created on Arbitrum One in the last N minutes on Uniswap v4, Uniswap v3: both tokens with symbol, name and decimals, fee tier, v4 hooks, whether it pairs with ETH, WETH or USDC, and quote liquidity where readable. Unvetted: many new pools are spam.

$0.01Base2
GET/arbitrum/nft

Metadata for an ERC-721 or ERC-1155 token on Arbitrum One: collection name, current owner (ERC-721), token URI, and the metadata JSON fetched and decoded from IPFS, Arweave, HTTPS or an inline data URI, with a browser-loadable image URL.

$0.008Base2
GET/arbitrum/token

Rug check and due-diligence snapshot of an ERC-20 token on Arbitrum One: a 0-100 risk score with reasons, name, symbol, decimals, supply, owner and whether ownership is renounced, upgradeable-proxy detection, owner-only functions found in the bytecode (mint, pause, blacklist, fee changes), and USD price, liquidity and FDV from the deepest WETH or USDC pool on Uniswap v3. Facts only, no buy or sell opinion.

$0.01Base2
GET/arbitrum/trades

Whale and large-trade tracker for an ERC-20 on Arbitrum One: every buy and sell in the last N minutes on the token's deepest WETH/USDC pools (Uniswap v3), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

$0.02Base2
GET/arbitrum/tx

Human-readable summary of a Arbitrum One transaction: status, block and time, sender and recipient, ETH value, gas used and fee, method selector, and decoded ERC-20 transfers with token symbols and amounts.

$0.005Base2
GET/arbitrum/wallet-profile

Who is this Arbitrum One address? Wallet age (first transfer), first funder, contract or EOA, ETH balance and nonce, the latest transfers in and out (native, ERC-20, NFTs), top counterparties by count, and recent large transfers in USD (ETH, WETH, USDC, USDT), from Alchemy's transfer index.

$0.01Base2
GET/base/allowance

ERC-20 allowance on Base: how much a spender may transfer from an owner, whether the approval is effectively unlimited, the owner's balance, and the amount the spender could move right now.

$0.005Base2
GET/base/balances

Native ETH balance of a Base wallet plus the balances of up to 20 ERC-20 tokens you list, formatted with each token's symbol and decimals, read live from Base.

$0.005Base2
GET/base/basename

Resolve a Basename (name.base.eth) to its Base address and profile records (avatar, description, url, Twitter, GitHub). Accepts "jesse", "jesse.base" or "jesse.base.eth".

$0.005Base2
GET/base/contract

Identify what lives at a Base address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and ETH balance.

$0.005Base2
GET/base/gas

Current Base gas conditions: block number, base fee, gas price and priority fee in gwei, and the estimated cost in ETH and USD of a native transfer and an ERC-20 transfer (Chainlink ETH/USD).

$0.005Base2
GET/base/new-pools

New trading pools created on Base in the last N minutes on Uniswap v4, Uniswap v3 or Aerodrome: both tokens with symbol, name and decimals, fee tier, v4 hooks, whether it pairs with ETH, WETH or USDC, and quote liquidity where readable. Unvetted: many new pools are spam.

$0.01Base2
GET/base/nft

Metadata for an ERC-721 or ERC-1155 token on Base: collection name, current owner (ERC-721), token URI, and the metadata JSON fetched and decoded from IPFS, Arweave, HTTPS or an inline data URI, with a browser-loadable image URL.

$0.008Base2
GET/base/token

Rug check and due-diligence snapshot of an ERC-20 token on Base: a 0-100 risk score with reasons, name, symbol, decimals, supply, owner and whether ownership is renounced, upgradeable-proxy detection, owner-only functions found in the bytecode (mint, pause, blacklist, fee changes), and USD price, liquidity and FDV from the deepest WETH or USDC pool on Uniswap v3 or Aerodrome. Facts only, no buy or sell opinion.

$0.01Base2
GET/base/trades

Whale and large-trade tracker for an ERC-20 on Base: every buy and sell in the last N minutes on the token's deepest WETH/USDC pools (Uniswap v3 or Aerodrome), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

$0.02Base2
GET/base/tx

Human-readable summary of a Base transaction: status, block and time, sender and recipient, ETH value, gas used and fee, method selector, and decoded ERC-20 transfers with token symbols and amounts.

$0.005Base2
GET/base/wallet-profile

Who is this Base address? Wallet age (first transfer), first funder, contract or EOA, ETH balance and nonce, the latest transfers in and out (native, ERC-20, NFTs), top counterparties by count, and recent large transfers in USD (ETH, WETH, USDC, USDT), from Alchemy's transfer index.

$0.01Base2
GET/business-days

Number of business days between two dates in a Canadian province or territory, excluding weekends and that province's statutory holidays (with weekend holidays moved to their observed weekday). Counts from the start date up to but not including the end date, and lists the holidays skipped.

$0.005Base2
GET/check

Is it safe to pay this address? One check before sending or accepting crypto: OFAC SDN sanctions screen, wallet age, EOA or contract, first funder and recent large transfers on Base, Ethereum, Arbitrum, Optimism or Polygon (wallet kind and activity on Solana), plus the token's 0-100 risk score when a token is given. Returns ok, caution or block with plain reasons and each check in full. Rules-based, not legal advice.

$0.02Base2
GET/check/lite

Is it safe to pay this address? The address-only version of /check: OFAC SDN sanctions screen, wallet age, EOA or contract, first funder and recent large transfers on Base, Ethereum, Arbitrum, Optimism or Polygon (wallet kind and activity on Solana), with the funder and counterparties screened too. Returns ok, caution or block with plain reasons. No token score (use /check for that). Rules-based, not legal advice.

$0.01Base2
GET/deployer

Who launched this token, and what happened to their other tokens? A creator's launch record on Base, Ethereum, Arbitrum, Optimism, Polygon or Solana from our own history of new pools: every token the wallet launched since 2026-10-23 with its risk score at launch and whether its liquidity was gone 24 hours and 7 days later, plus a verdict (repeat-rugger, prior-rug, serial-launcher, clean-so-far, too-new). Pass the deployer wallet or a token address. Not advice.

$0.005Base2
GET/eth/allowance

ERC-20 allowance on Ethereum: how much a spender may transfer from an owner, whether the approval is effectively unlimited, the owner's balance, and the amount the spender could move right now.

$0.005Base2
GET/eth/balances

Native ETH balance of a Ethereum wallet plus the balances of up to 20 ERC-20 tokens you list, formatted with each token's symbol and decimals, read live from Ethereum.

$0.005Base2
GET/eth/contract

Identify what lives at a Ethereum address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and ETH balance.

$0.005Base2
GET/eth/ens

ENS on Ethereum: resolve a name (vitalik.eth) to its address and profile records (avatar, description, url, Twitter, GitHub), or pass an address instead to get its primary ENS name. Uses ENS's universal resolver.

$0.005Base2
GET/eth/gas

Current Ethereum gas conditions: block number, base fee, gas price and priority fee in gwei, and the estimated cost in ETH and USD of a native transfer and an ERC-20 transfer (Chainlink ETH/USD).

$0.005Base2
GET/eth/new-pools

New trading pools created on Ethereum in the last N minutes on Uniswap v4, Uniswap v3: both tokens with symbol, name and decimals, fee tier, v4 hooks, whether it pairs with ETH, WETH or USDC, and quote liquidity where readable. Unvetted: many new pools are spam.

$0.01Base2
GET/eth/nft

Metadata for an ERC-721 or ERC-1155 token on Ethereum: collection name, current owner (ERC-721), token URI, and the metadata JSON fetched and decoded from IPFS, Arweave, HTTPS or an inline data URI, with a browser-loadable image URL.

$0.008Base2
GET/eth/token

Rug check and due-diligence snapshot of an ERC-20 token on Ethereum: a 0-100 risk score with reasons, name, symbol, decimals, supply, owner and whether ownership is renounced, upgradeable-proxy detection, owner-only functions found in the bytecode (mint, pause, blacklist, fee changes), and USD price, liquidity and FDV from the deepest WETH or USDC pool on Uniswap v3. Facts only, no buy or sell opinion.

$0.01Base2
GET/eth/trades

Whale and large-trade tracker for an ERC-20 on Ethereum: every buy and sell in the last N minutes on the token's deepest WETH/USDC pools (Uniswap v3), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

$0.02Base2
GET/eth/tx

Human-readable summary of a Ethereum transaction: status, block and time, sender and recipient, ETH value, gas used and fee, method selector, and decoded ERC-20 transfers with token symbols and amounts.

$0.005Base2
GET/eth/wallet-profile

Who is this Ethereum address? Wallet age (first transfer), first funder, contract or EOA, ETH balance and nonce, the latest transfers in and out (native, ERC-20, NFTs), top counterparties by count, and recent large transfers in USD (ETH, WETH, USDC, USDT), from Alchemy's transfer index.

$0.01Base2
GET/fx/convert

Convert an amount between two currencies at the European Central Bank daily reference rate, latest or for a past date, returning the rate used, the result, and the rate date.

$0.005Base2
GET/fx/rates

European Central Bank daily reference exchange rates for about 30 major currencies, from any base currency, latest or for a past date. Rates update once per working day; the response states which day.

$0.005Base2
GET/holidays

Statutory (general) holidays for a Canadian province or territory in a given year, using the province's local names, with the actual date and the weekday it is observed when it falls on a weekend.

$0.01Base2
GET/jobs/company

Open jobs at a company, from its own applicant tracking system's public job board: Greenhouse, Lever, Ashby, Workable, SmartRecruiters, Recruitee, BambooHR, Personio, Teamtailor, or Workday from a careers URL. Give a company name, website or job-board URL, with optional title, location and remote filters. Returns the newest 50 matching jobs with title, department, location, remote flag, salary when published, posting date and apply link, plus total counts.

$0.005Base2
GET/optimism/allowance

ERC-20 allowance on OP Mainnet: how much a spender may transfer from an owner, whether the approval is effectively unlimited, the owner's balance, and the amount the spender could move right now.

$0.005Base2
GET/optimism/balances

Native ETH balance of a OP Mainnet wallet plus the balances of up to 20 ERC-20 tokens you list, formatted with each token's symbol and decimals, read live from OP Mainnet.

$0.005Base2
GET/optimism/contract

Identify what lives at a OP Mainnet address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and ETH balance.

$0.005Base2
GET/optimism/gas

Current OP Mainnet gas conditions: block number, base fee, gas price and priority fee in gwei, and the estimated cost in ETH and USD of a native transfer and an ERC-20 transfer (Chainlink ETH/USD).

$0.005Base2
GET/optimism/new-pools

New trading pools created on OP Mainnet in the last N minutes on Uniswap v4, Uniswap v3 or Velodrome: both tokens with symbol, name and decimals, fee tier, v4 hooks, whether it pairs with ETH, WETH or USDC, and quote liquidity where readable. Unvetted: many new pools are spam.

$0.01Base2
GET/optimism/nft

Metadata for an ERC-721 or ERC-1155 token on OP Mainnet: collection name, current owner (ERC-721), token URI, and the metadata JSON fetched and decoded from IPFS, Arweave, HTTPS or an inline data URI, with a browser-loadable image URL.

$0.008Base2
GET/optimism/token

Rug check and due-diligence snapshot of an ERC-20 token on OP Mainnet: a 0-100 risk score with reasons, name, symbol, decimals, supply, owner and whether ownership is renounced, upgradeable-proxy detection, owner-only functions found in the bytecode (mint, pause, blacklist, fee changes), and USD price, liquidity and FDV from the deepest WETH or USDC pool on Uniswap v3 or Velodrome. Facts only, no buy or sell opinion.

$0.01Base2
GET/optimism/trades

Whale and large-trade tracker for an ERC-20 on OP Mainnet: every buy and sell in the last N minutes on the token's deepest WETH/USDC pools (Uniswap v3 or Velodrome), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

$0.02Base2
GET/optimism/tx

Human-readable summary of a OP Mainnet transaction: status, block and time, sender and recipient, ETH value, gas used and fee, method selector, and decoded ERC-20 transfers with token symbols and amounts.

$0.005Base2
GET/optimism/wallet-profile

Who is this OP Mainnet address? Wallet age (first transfer), first funder, contract or EOA, ETH balance and nonce, the latest transfers in and out (native, ERC-20, NFTs), top counterparties by count, and recent large transfers in USD (ETH, WETH, USDC, USDT), from Alchemy's transfer index.

$0.01Base2
GET/polygon/allowance

ERC-20 allowance on Polygon PoS: how much a spender may transfer from an owner, whether the approval is effectively unlimited, the owner's balance, and the amount the spender could move right now.

$0.005Base2
GET/polygon/balances

Native POL balance of a Polygon PoS wallet plus the balances of up to 20 ERC-20 tokens you list, formatted with each token's symbol and decimals, read live from Polygon PoS.

$0.005Base2
GET/polygon/contract

Identify what lives at a Polygon PoS address: wallet (EOA, including EIP-7702 delegation) or contract, which token standard it implements (ERC-20, ERC-721, ERC-1155), name and symbol, upgradeable-proxy implementation and admin, smart-wallet proxies, bytecode size, nonce and POL balance.

$0.005Base2
GET/polygon/gas

Current Polygon PoS gas conditions: block number, base fee, gas price and priority fee in gwei, and the estimated cost in POL and USD of a native transfer and an ERC-20 transfer (Chainlink POL/USD).

$0.005Base2
GET/polygon/new-pools

New trading pools created on Polygon PoS in the last N minutes on Uniswap v4, Uniswap v3: both tokens with symbol, name and decimals, fee tier, v4 hooks, whether it pairs with POL, WPOL or USDC, and quote liquidity where readable. Unvetted: many new pools are spam.

$0.01Base2
GET/polygon/nft

Metadata for an ERC-721 or ERC-1155 token on Polygon PoS: collection name, current owner (ERC-721), token URI, and the metadata JSON fetched and decoded from IPFS, Arweave, HTTPS or an inline data URI, with a browser-loadable image URL.

$0.008Base2
GET/polygon/token

Rug check and due-diligence snapshot of an ERC-20 token on Polygon PoS: a 0-100 risk score with reasons, name, symbol, decimals, supply, owner and whether ownership is renounced, upgradeable-proxy detection, owner-only functions found in the bytecode (mint, pause, blacklist, fee changes), and USD price, liquidity and FDV from the deepest WPOL or USDC pool on Uniswap v3. Facts only, no buy or sell opinion.

$0.01Base2
GET/polygon/tx

Human-readable summary of a Polygon PoS transaction: status, block and time, sender and recipient, POL value, gas used and fee, method selector, and decoded ERC-20 transfers with token symbols and amounts.

$0.005Base2
GET/polygon/wallet-profile

Who is this Polygon PoS address? Wallet age (first transfer), first funder, contract or EOA, POL balance and nonce, the latest transfers in and out (native, ERC-20, NFTs), top counterparties by count, and recent large transfers in USD (POL, WPOL, USDC, USDT), from Alchemy's transfer index.

$0.01Base2
GET/solana/token

Rug check and due-diligence snapshot of a Solana SPL or Token-2022 token: a 0-100 risk score with reasons, name, symbol, supply, mint and freeze authority, Token-2022 controls (permanent delegate, transfer fees, transfer hook, pausable), metadata mutability, top-holder concentration split into wallets and program accounts, and USD price, liquidity, volume and pools from Jupiter and DexScreener. Facts only, no buy or sell opinion.

$0.01Base2
GET/solana/wallet

Portfolio and activity of a Solana wallet: SOL and every SPL and Token-2022 balance with USD values from Jupiter, sorted by value, with dust, unpriced and empty token accounts summarized, plus the newest transaction time, transactions in the last 24 hours, and the oldest transaction in the newest 1,000, with a flag when history goes further back.

$0.005Base2
GET/tax

Canadian sales tax breakdown for an amount in a province or territory: GST, HST, PST, RST or QST with each rate and amount rounded to the cent, plus the total. Rates are looked up for the given date (default today), so historical changes such as Nova Scotia's 2025 HST cut are handled.

$0.005Base2
GET/token

Is this token safe? Rug check for any token on Base, Ethereum, Arbitrum, Optimism, Polygon or Solana: a 0-100 risk score with plain reasons (mint, freeze, blacklist, fee, pause or trading-switch powers, upgradeable code, holder concentration, thin or missing liquidity), the facts behind it, and USD price and liquidity. Each answer includes a fingerprint; sending it back as since returns what changed. Rules-based, not advice.

$0.01Base2
POST/verdict

Rug Radar verdict for a token on Base, Ethereum, Arbitrum, Optimism, Polygon or Solana: a grade (CLEAN, MID, SKETCHY, RUGGY), a one-liner, a short take and a shareable card, built from real onchain facts: the 0-100 risk score with its reasons and the deployer's record (did their earlier tokens lose liquidity?). Same call shape as quest verdicts: POST tokenAddress with an optional requestKey, echoed back. Rules-based, not financial advice.

$0.01Base2
GET/watchlist

Re-check up to 5 tokens you hold or watch in one call, on Base, Ethereum, Arbitrum, Optimism, Polygon or Solana: each token's 0-100 risk score, level, reason codes, price, liquidity and a fingerprint. Send the fingerprints back as since to get what changed (new risks, owner or authority changes, liquidity or price moves of 10%+) and a short list of alerts. One price for the whole list, made for polling positions on a schedule. Rules-based, not advice.

$0.01Base2
GET/polygon/trades

Whale and large-trade tracker for an ERC-20 on Polygon PoS: every buy and sell in the last N minutes on the token's deepest WPOL/USDC pools (Uniswap v3), with USD size, side, wallet and transaction for the largest trades, buy/sell volume and net flow, and the wallets that bought or sold the most.

$0.02Base1

Is this your project? Suggest an edit.