# Using URL parameters

## Tracking and UTM fields

### Macros

You can access UTM values using macros within your templates and form fields.

```markup
<p>${utm_campaign}</p>
```

## Other URL parameters

If a param is not the list of pre-approved parameters above under [Tracking and UTM fields](/themes-and-custom-templates/using-url-parameters.md#tracking-and-utm-fields), then that URL parameter will need to be whitelisted in your project settings.

But once whitelisted, you can use them in your templates

### Macros

You can access these whitelisted URL parameters in your template using macros.

Example: `https://www.example.com/?campaignid=12345`

```markup
<p>${urlparam_campaignid}</p>
```

Would output

```markup
<p>12345</p>
```

## Use in templating

Both UTM (campaign parameters) and the other URL parameters are available within jinja templates in the same place.

Example: `https://www.example.com/?promo=august&utm_campaign=email`

```markup
<p>Promo: {{ request_params.promo }}</p>
<p>Campaign: {{ request_params.utm_campaign }}</p>
```

Would output

```markup
<p>Promo: august</p>
<p>Campaign: email</p>
```

To easily access these values in javascript, you can output request\_params to JSON

```html
<script>
var requestParams = {{ request_params|tojson|safe }};
</script>
```


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