> For the complete documentation index, see [llms.txt](https://docs.tebex.io/developers/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tebex.io/developers/tebex.js/checkout/events.md).

# Events

Events are fired by `Tebex.checkout` upon specific actions to alert your frontend and enable you to take action when required. These events should **not** be used to confirm actual receipt of payment - you should use [Webhooks](/developers/webhooks/overview.md) instead.

To add a checkout event callback, use `Tebex.checkout.on()` . The first argument to this function should be the name of the event to listen to, and the second argument should be a function to call when that event is fired:

```javascript
Tebex.checkout.on("payment:complete", (event) => {
    console.log("Payment completed!", event);
});
```

Available events are as follows:

<table><thead><tr><th width="189.74609375">Name</th><th>Fired Upon</th></tr></thead><tbody><tr><td><code>"open"</code></td><td>The portal popup opening after calling <code>Tebex.checkout.launch().</code></td></tr><tr><td><code>"close"</code></td><td>The portal popup closing after being dismissed by the user.</td></tr><tr><td><code>"payment:complete"</code></td><td>The customer has successfully completed their payment.</td></tr><tr><td><code>"payment:error"</code></td><td>The customer experienced an error, such as incorrect card details or insufficient funds, when making a payment.</td></tr></tbody></table>

All events that can be listened to with [`Tebex.checkout.on()`](#events) are exposed on the element as custom DOM events, which means you can use addEventListener to subscribe to them:

```html
<html>
    <body>
        <tebex-checkout id="checkout"></tebex-checkout>
    </body>
    <script>
        const checkout = document.getElementById("checkout);
        
        checkout.addEventListener("open", () => {
            console.log("checkout opened");
        });

        checkout.addEventListener("close", () => {
            console.log("checkout closed");
        });

        checkout.addEventListener("payment:complete", (event) => {
            console.log("payment completed", event);
        });

        checkout.addEventListener("payment:error", (event) => {
            console.log("payment errored", event);
        });
    </script>
</html>
```


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