# Client-side AJAX using JSON
Very often, many developers, including *myself* in the past, normally all along we were using jQuery's `$.ajax` and sending in JSON with `dataType: 'json'` without really sending the `content-type` as a JSON string which is supposed to be `application/json` - instead we were actually sending in a regular POST (`application/x-www-urlencoded`) and decoding it from the PHP side as `$_POST`.
So, if you have this script, **post.php**, in a folder :
```php
```
and in **jqurey-ajax.html** :
```xml
jQuery AJAX
```
we get :
![](https://cdn.hashnode.com/res/hashnode/image/upload/v1677646306335/cc06362a-78b9-41cc-981b-5afac656c1bc.png align="center")
## The Real JSON
### For sending in non-JSON requests
Have this script, run.php, in the same folder :
```php
```
If you have this HTML file in the same folder as client.html
```javascript
let url = "http://localhost:8989/run.php";
const formData = new FormData();
formData.append("username", "john");
formData.append("password", "a5y6e7Chk65kmFWeK5F5");
const run = async() =>
{
let response = await fetch(url,
{
method: "POST",
headers:
{
"Content-Type": "application/x-www-urlencoded",
},
body: new URLSearchParams(formData),
});
}
run();
```
If you run \`php.exe -S [localhost:8989](http://localhost:8989)\`, you should get this in the response of the URL request you'll see in console :
```plaintext
Array
(
[username] => john
[password] => a5y6e7Chk65kmFWeK5F5
)
```
### For sending in JSON requests
run.php :
```php
```
client.html :
```javascript
let url = "http://localhost:8989/run.php";
const formData = new FormData();
formData.append("username", "john");
formData.append("password", "a5y6e7Chk65kmFWeK5F5");
const run = async() =>
{
var object = {};
formData.forEach((value, key) => object[key] = value);
let response = await fetch(url,
{
method: "POST",
headers:
{
"Content-Type":"application/json",
},
body: JSON.stringify(object)
});
}
run();
```
We get :
```plaintext
username "john"
password "a5y6e7Chk65kmFWeK5F5"
```
I haven't *echo*ed a JSON string to the output in the above 2 examples because I just wanted show how it's communicated - I'll leave it up to you to print a JSON string on the server-side for the client to fetch as response.