---
title: "Client.exists(keys) | Grafana k6 documentation"
description: "Returns the number of `key` arguments that exist."
---

# Client.exists(keys)

Returns the number of `key` arguments that exist. Note that if the same existing key is mentioned in the argument multiple times, it will be counted multiple times.

### Parameters

Expand table

| Parameter | Type      | Description                         |
|-----------|-----------|-------------------------------------|
| `keys`    | string\[] | the keys to check the existence of. |

### Returns

Expand table

| Type              | Resolves with                                                                                            | Rejected when |
|-------------------|----------------------------------------------------------------------------------------------------------|---------------|
| `Promise<number>` | On success, the promise resolves with the `number` of keys that exist from those specified as arguments. |               |

### Example

JavaScript ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

```javascript
import redis from 'k6/x/redis';

// Instantiate a new redis client
const redisClient = new redis.Client('redis://localhost:6379');

export default async function () {
  let exists = await redisClient.exists('mykey');
  if (exists === true) {
    throw new Error('mykey should not exist');
  }

  await redisClient.set('mykey', 'myvalue', 0);

  exists = await redisClient.exists('mykey');
  if (exists === false) {
    throw new Error('mykey should exist');
  }

  await redisClient.del('mykey');
}
```