NK Nyckeln Mastercard API Access & Open Banking

Want programmatic visibility into your NK Nyckeln Mastercard? open-banking.io turns your everyday card statements into structured, machine-readable data — without certificates, PSD2 licences, or a sandbox application. It is a zero-knowledge EU/UK open-banking service covering 2,600+ banks and card issuers, where your NK Nyckeln Mastercard data is encrypted and only ever decrypted on your own device with a key that never leaves it.

The NK Nyckeln Mastercard is a Swedish personal card, so open-banking.io exposes personal account access for it. Its BIC is not published (n/a), and each authorisation you grant stays valid for up to 180 days before you re-approve.

How to connect NK Nyckeln Mastercard

Connecting happens entirely in 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 encryption keys are generated locally on your device at this moment; open-banking.io only ever sees your public key.
  3. In the dashboard, choose NK Nyckeln Mastercard and select the personal account type.
  4. You are redirected to NK Nyckeln Mastercard's own secure consent screen, where you log in and approve access directly with the issuer under PSD2.
  5. Once approved, your account and transactions sync back into your dashboard.

Because the login and approval happen on the issuer's side, open-banking.io never touches your card credentials.

Access your data

After your NK Nyckeln Mastercard is connected, reading the data programmatically is an optional developer step. Open the Developers page, create an API key, and export a credentials.json — this bundles your 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. Every request carries the X-Api-Key header, and each response is decrypted locally with your own key. Without that private key, the API key alone returns nothing but ciphertext — open-banking.io's servers cannot read your NK Nyckeln Mastercard data. Note the CLI and SDK only read and sync connections you already made in the dashboard; there is no connect command.

At roughly EUR 3/month, it is a low-cost way to keep card data flowing into your own tools.

FAQ

Do I need a PSD2 licence or certificate?

No. open-banking.io is certificate-free — you authorise access as the cardholder on NK Nyckeln Mastercard's own consent screen, with no eIDAS certificate required.

Can open-banking.io read my NK Nyckeln Mastercard data?

No. It is zero-knowledge and holds only your public key. Data is decrypted on your device with a private key that only you possess.

How long does my authorisation last?

Up to 180 days per approval for NK Nyckeln Mastercard, after which you simply re-approve from the dashboard.

Ready to start? Visit open-banking.io.