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Calculate gross profit, profit margin (profit as % of price) and markup (profit as % of cost) from a unit cost and sell…Docs not supplied

Calculate return on investment: profit (or loss) and the percentage return relative to the initial amount invested. Use…Docs not supplied

Validate an International Bank Account Number: country code, country-specific length and the ISO 7064 MOD 97-10 check d…Docs not supplied

One-call on-chain profile of any Ethereum or Base wallet via Blockscout: native balance, transaction and transfer count…Docs not supplied

Generate a QR code for any text, URL or crypto address: returns ready-to-embed SVG markup and a data URI, with configur…Docs not supplied

Explain what an EVM transaction would actually do: decodes the calldata (ERC-20 transfers/approvals via known ABIs, unk…Docs not supplied

Convert between wei, kwei, mwei, gwei, microether, milliether and ether with exact BigInt arithmetic. Decimal strings o…Docs not supplied

Fetch an RSS or Atom feed and return normalized JSON items: title, link, publication date (ISO) and summary. Server-sid…Docs not supplied

Calculate a transaction's gas fee: gas units × gas price (gwei) gives the ETH cost, multiplied by the ETH price for USD…Docs not supplied

Convert integers between any bases from 2 to 36 — binary, octal, decimal, hexadecimal and beyond — with BigInt precisio…Docs not supplied

Turn a cron expression into plain English, validate it, and compute the exact next execution times. Deterministic — the…Docs not supplied

Live foreign-exchange reference rates from the European Central Bank (via frankfurter.dev): a full rate table against a…Docs not supplied