What a routing number identifies
An ABA routing number identifies a U.S. financial institution or processing endpoint. It does not identify an individual bank account.
TechFinity toolkit
Bank Routing Number Lookup
Validate a U.S. ABA routing number locally, then retrieve institution details through the configured provider.
Lookup routing number
The provider API key is kept server-side in private configuration and is never sent to the browser.
Local validation
Before contacting the provider, this page checks the official nine-digit weighted checksum. This catches many typographical errors and avoids unnecessary external lookups.
Checksum formula
Digits are weighted in a repeating 3-7-1 pattern; the weighted sum must be divisible by 10.
Verify critical payments
For high-value transactions, independently confirm routing and account instructions with the intended institution or recipient.