> **Description:** Detailed explanations and visual flow diagrams demonstrating how the PSP API integrates with online payment systems, including payment initiation, processing, and completion flows.

# How the Vipps PSP API works online

How payments in web shops or merchant websites work with the Vipps PSP API.

## Details

### 1. Customer selects their payment method

Give the customer the option to pay with Vipps in your webshop or app.

Screenshot: Mobile merchant cart page showing items, cost, and a "Pay with Vipps" button.

### 2. Customer enters their phone number and logs in

When they select Vipps, initiate a payment with:
[`POST:/psp/v3/psppayments/init/`](https://developer.vippsmobilepay.com/redocusaurus/psp-swagger-id.yaml).

If the payment was started from a mobile device, the Vipps app will automatically open.

If the payment was started on a desktop device, the
[landing page](https://developer.vippsmobilepay.com/docs/knowledge-base/landing-page.md) will open.
There, the customer enters their phone number and clicks *Next* to send the payment request to the app on their phone.

Screenshot: Vipps landing page. Left panel: phone number entry (Norwegian +47 prefix) with "Remember my number" checkbox. Right panel: waiting screen with "Open Vipps" and a countdown timer.

### 3. Customer confirms the payment in the app

A push notification appears on the customer's phone. They log in to Vipps and confirm the payment.
The Vipps PSP API automatically reserves the payment and provides confirmation of the successful payment.

Screenshot: Vipps app payment screen showing payment to Merchant with order description, Visa Spendings card, and a Pay button.

### 4. The merchant's shop confirms the order

After the customer has approved the payment in the app:

* If the payment was started on a mobile device, the store page or app will open again and confirm that the order was successful.
* If the payment was started on a desktop device, the user can go back to the webpage where it will confirm that the order was successful.

Screenshot: Merchant webshop order confirmation page showing "Thank you for your order" with a green checkmark and an order summary with free shipping.

To determine that the user has authorized the payment, poll with the
[`GET:/psp/v3/psppayments/{pspTransactionId}/details`](https://developer.vippsmobilepay.com/redocusaurus/psp-swagger-id.yaml)
request. See the [guidelines for polling](https://developer.vippsmobilepay.com/docs/knowledge-base/polling-guidelines.md).

### 5. The merchant completes the order and shipping

The merchant completes the order and ships it to the customer.

### 6. Capture the payment

The merchant captures the order through the PSP, who captures the payment through the Vipps PSP API.

## More information

For technical details, see the [Vipps PSP API guide](https://developer.vippsmobilepay.com/docs/APIs/psp-api/vipps-psp-api.md).

> **Full site overview:** For every page in this documentation, read [https://developer.vippsmobilepay.com/llms.txt](https://developer.vippsmobilepay.com/llms.txt).