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# PTTL

> Return the expiration in milliseconds of a key.

## Arguments

<ParamField body="key" type="string" required>
  The key 
</ParamField>

## Response

<ResponseField type="integer" required>
  The number of milliseconds until this expires, negative if the key does not exist or does not have an expiration set.
</ResponseField>

<RequestExample>
```ts Example
const millis = await redis.pttl(key);
```
</RequestExample>