How to Use the DNS Propagation Checker
After changing DNS records, use the propagation checker to see which resolvers have the new values and which are still showing old data.
How to Use the DNS Propagation Checker
When you change a DNS record, the new value doesn't appear everywhere instantly. DNS uses a caching system - each resolver holds the previous answer for a time defined by the record's TTL (Time To Live). The propagation checker shows you which resolvers around the world have already picked up your changes.
When to Use It
- After pointing a domain to a new hosting server (A record change)
- After moving to Cloudflare or another CDN (NS record change)
- After switching email providers (MX record change)
- After updating SPF, DKIM, or DMARC records (TXT record change)
- After adding a domain verification token (TXT record)
Running a Propagation Check
- Go to Tools → DNS Propagation Checker
- Enter the domain or hostname (e.g.
example.comorshop.example.com) - Select the record type you changed: A, AAAA, MX, TXT, CNAME, NS, or SOA
- Click Check Propagation
The tool queries multiple DNS resolvers globally and shows the response each one returned.
Reading the Results
Each resolver in the results shows:
| Column | What It Shows |
|---|---|
| Location | Region/country of the resolver |
| Result | The value the resolver returned |
| Status | ✅ Propagated (matches expected) / ⏳ Old value / ❌ Error |
| Response time | How fast that resolver answered |
Look at the result column. If most resolvers show your new IP address (or new value), propagation is substantially complete. A few stragglers with old values is normal and will resolve as their caches expire.
DNS TTL and How Long Propagation Takes
TTL is measured in seconds. It tells resolvers how long to cache the record before re-querying:
| TTL | Cache Duration | Typical Use |
|---|---|---|
| 300 | 5 minutes | During migrations - low TTL speeds up propagation |
| 3600 | 1 hour | Normal records |
| 86400 | 24 hours | Stable, rarely-changed records |
If your old record had a 24-hour TTL, resolvers can cache it for 24 hours. That means full propagation can take up to 24 hours - even though most resolvers will refresh sooner.
Best practice before a planned migration:
- Reduce your TTL to 300 seconds (5 minutes) at least 24 hours before the change
- Wait 24 hours for the low TTL to propagate
- Make your DNS change
- Wait 5-10 minutes for propagation
- Verify with the propagation checker
- After migration is confirmed, raise the TTL back to 3600 or 86400
Checking Specific Record Types
A Record (IP Address)
After moving a website to a new server, check the A record to see if your domain is resolving to the new IP globally.
MX Record (Email)
After switching email providers, check MX to confirm the new mail server is live. Don't cancel your old email service until MX propagation is complete.
TXT Record (SPF, DKIM, Verification Tokens)
Google Workspace, Microsoft 365, and most services require a TXT record for domain verification. Use the propagation checker to confirm the TXT record is visible before clicking "Verify" in the service's admin console.
NS Record (Nameservers)
After transferring your domain or changing DNS providers, NS propagation can take up to 48 hours. Check NS propagation to see when the new nameservers are live.
CNAME Record
After adding a subdomain alias (e.g. shop.example.com → mystore.shopify.com), verify the CNAME is live before directing traffic to the subdomain.
Why Some Resolvers Show Different Results
- TTL not expired yet - resolver cached the old value; it will update when the TTL expires
- Resolver using old cached negative response - some resolvers cache NXDOMAIN (not found) answers; takes time to clear
- Regional resolver delay - some geographic regions propagate slower due to infrastructure paths
Seeing 10-20% of resolvers with old values is normal and not a problem. If 50%+ still show old values after 4 hours, double-check that you saved the DNS change correctly at your DNS provider.