Gránit Bank Open Banking & API Access (Hungary)

Reaching Gránit Bank account data used to mean wrestling with certificates, sandbox registrations and PSD2 paperwork. open-banking.io removes all of that. It links to Gránit Bank (BIC GNBAHUHBXXX) through a single, encrypted dashboard, so your Hungarian business or personal balances and transactions flow into one place — and the decryption key that unlocks them never leaves your device.

Everything is zero-knowledge and certificate-free. Our servers store only your public key, so what lives on them is ciphertext no one but you can read. You approve access directly on Gránit Bank's own login, and a single consent stays valid for up to 180 days before you renew it.

How to connect Gránit Bank

Connecting happens entirely inside the open-banking.io dashboard — there is no API call, code or key involved in this step:

1. Sign up for an open-banking.io account.
2. Set your encryption passphrase. Your keys are generated locally on your own device from this passphrase.
3. In the dashboard, pick Gránit Bank and choose the account type you want to link — business or personal.
4. You are redirected to Gránit Bank's own secure login, where you approve access under PSD2.
5. Your accounts sync back into your dashboard, ready to view and refresh.

That is the whole flow. No developer redirect, no client credentials, no manual endpoint wiring.

Access your data

Once Gránit Bank is connected, reading the data programmatically is an optional step for developers. Open the Developers page, create an API key, and export a credentials.json — this bundles the API key together with your private decryption key. From there you can use the CLI (openbanking accounts, openbanking transactions, openbanking sync), an SDK, or the REST API directly.

Every request carries the X-Api-Key header, and each response is decrypted locally with your own key. The key alone, without your private key, returns only ciphertext — which is exactly why the model stays zero-knowledge. Note there is no connect command: the CLI and SDK only read and sync connections you already established in the dashboard.

All of this runs on a flat subscription of roughly EUR 3/month, covering Gránit Bank and 2,600+ other EU/UK banks.

Do I need a developer account to link Gránit Bank?

No. Connecting is done in the dashboard by approving access on Gránit Bank's consent screen. API keys are only for reading data afterwards.

How long does Gránit Bank access last?

A single PSD2 consent remains active for up to 180 days, after which you simply re-approve it.

Can open-banking.io see my Gránit Bank transactions?

No. Data is decrypted only on your device with a key you hold. Our servers keep just your public key and store ciphertext.

Ready to start? Visit open-banking.io.