# Using JSONPath to validate numbers with specific initial digits

[JSONPath](/documentation/connectors-and-triggers/double-braces/double-braces-functions/json-functions.md) is a powerful tool for querying and filtering JSON data. It allows you to easily extract specific data from a JSON object or array, making it a valuable tool for developers and data analysts alike. 

In the following steps, you will learn how to use JSONPath to check whether a specific number starts with 0, 1, 2, or 3. This can be useful in situations where you need to filter out certain data or perform conditional operations based on the starting digits of a number.

## Validating numbers with JSONPath

To use JSONPath to check whether a number begins with 0, 1, 2 or 3, you can use the following expression:

```json
$[?(@.body.orderId =~ /^0.*/i || @.body.orderId =~ /^1.*/i || @.body.orderId =~ /^2.*/i || @.body.orderId =~ /^3.*/i)]
```

Let's break down this expression to understand how it works:

* `[ ]`: Used for filtering.
* `?`: Indicates a filter expression.
* `@.body.orderId`: Represents the path to the orderId field in the JSON structure.
* `=~`: Serves ad the regex match operator in JSONPath.
* `/^0.*/i`: Checks if the orderId starts with 0, 1, 2, or 3 (case-insensitive).
* `||`: Acts as  the logical OR operator, combining multiple conditions.

If the number meets this condition, it will be returned by the JSONPath query. Otherwise, it will be excluded from the results.

### Example

Let's say we have the following JSON data:

```json
{ "body": { "orderId": "12345" } }
```

Applying the JSONPath expression to this object would return a match, as the `orderId` (12345) starts with 1.


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