> ## Documentation Index
> Fetch the complete documentation index at: https://docs.alumio.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Format to form URL encoded

> Converts the context data into form url encoded string.

Turns your data into a form URL encoded string, the `key=value&key=value` format that web forms and many APIs expect in a request body. Each field becomes a `name=value` pair, the pairs are joined with `&`, and any characters that are not safe in a URL are encoded. The only choice is how spaces are written, which differs between two web standards.

This documentation describes: [Schema](/schemas/serializer/form-urlencoded)

## Fields

**Encoding type**

Optional

Which standard to follow when encoding spaces and special characters:

* **RFC 1738 Spaces to +** writes spaces as a plus sign (`+`). This is the default and what most web forms expect.
* **RFC 3986 Spaces to %20** writes spaces as `%20`, the stricter modern form some APIs require.

## Sample data

| Field | Value |
| - | - |
| Encoding type | RFC 1738 Spaces to + |

Input:

```json theme={null}
{ "first_name": "Jane Doe", "city": "Den Bosch", "tags": ["new", "vip"] }
```

Output:

```json theme={null}
"first_name=Jane+Doe&city=Den+Bosch&tags%5B0%5D=new&tags%5B1%5D=vip"
```

Spaces became `+`, and the nested list `tags` was flattened into `tags[0]` and `tags[1]` (with the brackets encoded as `%5B` and `%5D`).

```json Configuration theme={null}
{
  "prototype": "form-urlencoded",
  "parameters": {
    "encodingType": 1
  }
}
```


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