Use PTTL to read how much longer a key will live, in milliseconds.
The reply is -1 when the key exists but has no expiration and -2 when the key does not exist, so a missing key and a permanent one are easy to tell apart. It is the millisecond form of TTL, and the extra precision matters for short-lived keys such as locks, where rounding to whole seconds hides most of the remaining lifetime.
Syntax#
Arguments#
| Argument | Required | Repeatable | Description |
|---|---|---|---|
<key> | Yes | No | Redis key targeted by the command. |
Important points#
- Negative integer replies are sentinel values, not durations or timestamps; see the response description for missing or persistent data.
Response#
The reply reports the result of the operation. Error replies have the same shape in RESP2 and RESP3 and are surfaced as exceptions by the SDKs below.
| Protocol | Reply |
|---|---|
| RESP2 | Integer: remaining lifetime in milliseconds, -1 if the key has no expiration, -2 if the key does not exist |
| RESP3 | Integer: remaining lifetime in milliseconds, -1 if the key has no expiration, -2 if the key does not exist |
Client libraries often decode bulk strings, maps, sets, and numeric strings into language-native values. The table describes the Redis wire reply.
Examples#
TCP examples use the TLS REDIS_URL from the Upstash console. REST examples use UPSTASH_REDIS_REST_URL and UPSTASH_REDIS_REST_TOKEN.