DNS Tools

TTL Checker

See how long resolvers cache each of a domain's key DNS records.

Not sure what to enter? Try an example: google.com

Free & instant No signup How to use FAQ

Enter a domain to read the TTL of its A, AAAA, MX and NS records, so you know how quickly a change will reach visitors.

What is DNS TTL?

TTL (Time To Live) is the number of seconds resolvers may cache a DNS record before asking again. A long TTL (for example 86400 = 1 day) reduces lookups but makes changes slow to spread; a short TTL (300 = 5 minutes) lets changes take effect quickly.

How to check DNS TTL values

Enter the domain in the box above.
Click Check TTL.
Read the TTL of the A, AAAA, MX and NS records.
Before a planned migration, lower the TTL a day in advance so the switch-over propagates quickly, then raise it again afterwards.

Related checks

To watch a change spread after it is made, use the DNS Propagation Checker.
To see the zone's default timers, use the SOA Record Lookup.

Long TTLs make a site faster to resolve, short TTLs make changes go live sooner. Lower them a day before a migration and raise them again afterwards - JustChecker shows you when the change has taken effect.

Frequently Asked Questions

An hour (3600 seconds) is a sensible everyday value. Use 300 seconds when you expect to change a record soon, and longer values for records that almost never change.

Answers from a caching resolver show the time left until its copy expires, which counts down. Ask again a little later and the number will have dropped further, then reset.

Barely. Visitors may need a DNS lookup slightly more often, which costs a few milliseconds. Very low values like 30 seconds are rarely worth it for a normal website.

Share this tool:

Need a website for your business? Only $599