DNS TTL Explained: Why Your Website Update Is Delayed
You update your A Record to point to a new server. You hit save. You wait 10 minutes. Nothing changes.
Why? Because of a small number next to your record called TTL.
TTL stands for Time To Live.
It sounds dramatic, but it simply means: "How long should this information live in the cache before it expires?"
The "Expiration Date" Analogy
Imagine your DNS record is a carton of milk in your fridge.
- The Server (The Store): Has the fresh milk.
- Your Computer (The Fridge): Keeps a copy of the milk so you don't have to drive to the store every time you want cereal.
The TTL is the expiration date stamped on that milk.
If the TTL is 24 hours (86,400 seconds), your computer will keep using that old milk for a full day, even if the store starts selling a new brand.
Only after the 24 hours are up will your computer throw it away and go back to the store (DNS Server) to ask for the new information.
Common TTL Values
TTL is always measured in seconds.
- 86400 (24 Hours): Standard for stable websites. It reduces the load on your server because visitors only look up your IP once a day.
- 3600 (1 Hour): A good middle ground. If you break something, it fixes itself in an hour.
- 300 (5 Minutes): Used for testing or migrations.
The "Migration Trick" (Pro Tip)
If you plan to move your website to a new host next week, do this today:
- Log in to your DNS dashboard.
- Edit your A Record.
- Change the TTL from Automatic (or 14400) to 300.
- Wait 24 hours.
Now, when you actually move your site tomorrow, everyone in the world will see the change in just 5 minutes! Once the move is done, you can set the TTL back to normal (3600 or higher).
Conclusion
TTL is the volume knob for your DNS propagation. Keep it high for speed and stability, but turn it low when you are making changes. Mastering this setting is the difference between a smooth migration and 24 hours of panic.
Curious about your current settings?
