I built a free BSB validation API for Australian devs

I Built a Free BSB Validation API for Australian Devs If you've ever built a payment form, payroll system, or anything that touches Australian bank transfers, you've probably had to deal with BSB numbers. BSBs (Bank State Branch codes) are the 6-digit numbers that identify Australian bank branches. Every domestic transfer needs one. And yet there's no decent free API to validate them — until now. The problem A few months ago I was building a payment feature for a marketplace platform. Users were entering BSB numbers manually, and we had no way to validate them before submitting to Stripe. The options were: AusPayNet (the official source) — provides a CSV download, no API Existing BSB lookup sites — no API, just UI Building our own — parse the CSV, host it somewhere, build an endpoint So I built it. And then I thought, why not just make it public? What I built FindBSB — a free JSON API for Australian BSB lookups. No API key required. No signup. Just HTTP. Base URL: https://findbsb.com.a