TTL

TTL

TTL key

Available since:

1.0.0

Time complexity:

O(1)

ACL categories:

@keyspace, @read, @fast,

Returns the remaining time to live of a key that has a timeout. This introspection capability allows a Redis client to check how many seconds a given key will continue to be part of the dataset.

In Redis 2.6 or older the command returns -1 if the key does not exist or if the key exist but has no associated expire.

Starting with Redis 2.8 the return value in case of error changed:

• The command returns -2 if the key does not exist.
• The command returns -1 if the key exists but has no associated expire.

See also the PTTL command that returns the same information with milliseconds resolution (Only available in Redis 2.6 or greater).

Return

Integer reply: TTL in seconds, or a negative value in order to signal an error (see the description above).

Examples

SET mykey "Hello"
EXPIRE mykey 10
TTL mykey

History

• Starting with Redis version 2.8.0: Added the -2 reply.