TTL (time-to-live) indicates how long a record is cached by a DNS server, like your ISP (Internet Service Provider).
TTL is set in seconds, and the lowest value possible is 600 seconds (10 minutes). The highest possible value is 86400 seconds (24 hours). If you leave the field empty, the default value is 3600 seconds (1 hour).
Minimum TTL value: 600 seconds (10 minutes)
Maximum TTL value: 86400 seconds (24 hours)
Default TTL value: 3600 seconds (1 hour)