Validate IBAN structure, length, and mod-97 check digits for 80+ countries. Catch transfer typos before money moves — local ibantools work, free, no signup.
Content reviewed October 2026 · About Toolzum
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Validate CSV structure — flag rows with wrong column counts and empty cells before import. Catch bad rows locally — free, no signup.
Validate OAuth state parameters for format, length, and age — catch CSRF holes before they ship. Nothing leaves your browser.
Country length rules plus mod-97 check digits computed from rearranged digits. Valid structure passes; typos fail mathematically — no bank query needed.
No — structure valid only. Existence and ownership verify via bank confirmation (Confirmation of Payee where available).
80+ official IBAN registries with per-country lengths and formats. Non-IBAN countries (US, India) use local systems instead.
No — validation runs locally in your browser with ibantools. Numbers never leave your device — still, prefer test IBANs for trials.
Yes — the placeholder GB29 NWBK 6016 1331 9268 19 validates: spaces are stripped and letters uppercased before the mod-97 checksum runs. Change the final 9 to 8 and it fails, proving the check is purely mathematical. A valid structure still doesn’t mean the account exists — confirm with the bank.
Currency Converter
Converts between 160+ currencies when online — live rates refresh hourly from the server, with 12 quick-pick majors pinned on top. Offline, the same 12 convert from labeled fallback rates.
Invoice Generator
Produces printable invoices with editable line items, a single tax rate, notes, and sender/client blocks. Print to PDF or download a plain-text copy. Figures never leave your device — every calculation runs locally in your browser.