Choosing a TTL
The number that decides how long the internet remembers an answer you have already changed.
Updated 02 Sept 2026
Every record carries a টিটিএল — the number of seconds a resolver may keep the answer before asking again. It is the difference between a change that reaches everyone in five minutes and one that takes a day.
What the number costs you
A long টিটিএল means fewer lookups and slightly faster pages for repeat visitors. A short one means changes land quickly and every visitor pays a lookup more often. Neither is a setting you optimise; it is a setting you match to what you are about to do.
Before a move, shorten it
Lower the টিটিএল on the records you are about to change, wait for the old value to expire, and only then make the change. Drop it to 300 a day ahead of a server move and the switch is nearly invisible. Raise it back afterwards.
Everyday values
3600 — one hour — is a reasonable default for a record you rarely touch, and it is what a new record gets here. 300 is right while you are working. Anything under 60 is ignored by enough resolvers to be a false comfort.
Why is my change still not visible?
Something is still holding the old answer, and it expires on its own. Checking from a phone on mobile data is the quickest way to tell a caching problem from a broken record: if the new answer appears there and not on your office connection, nothing is wrong with the record. My site is down walks the rest of it.
Does a low TTL slow my site down?
Not measurably. A lookup is a few milliseconds and only the first visit in each window pays it. The reason not to leave everything at 300 is load on the nameservers, not the visitor experience.