DNS Propagation Checker

About this tool

The DNS Propagation Checker queries three public DNS resolvers — Cloudflare (1.1.1.1), Google (8.8.8.8) and Quad9 (9.9.9.9) — at the same time over DNS-over-HTTPS and lists the answer each one returns for a domain and record type. After you change an A record, MX record or name servers, resolvers keep serving the old value until its TTL expires, so comparing them shows whether these major caches have the new record yet. Choose A, AAAA, CNAME, MX, TXT or NS. The requests go directly from your browser to the three resolvers, which see the name you look up. Each resolver is anycast, so its answer comes from the site nearest to you rather than from fixed regions. A resolver with no answer shows “NXDOMAIN / no record”; a failed request shows its error.

Why use it

• Queries three major public resolvers in parallel in one click.

• Covers the record types most often changed: A, AAAA, CNAME, MX, TXT and NS.

• Shows each resolver's raw answer side by side, so stale caches are easy to spot.

• Helps diagnose propagation delays after DNS changes.

How to use

1. Enter the domain or hostname you want to check (an http:// prefix or path is removed).
2. Pick the record type: A, AAAA, CNAME, MX, TXT or NS.
3. Click Check propagation or press Enter to query Cloudflare, Google and Quad9 at once.
4. Compare the records listed for each resolver; differing values mean some caches still hold the old record.
5. Re-run the check later — once the old TTL has expired, all three should agree.

When it helps

• Verifying that a DNS record change has propagated globally after a server migration.
• Checking whether a domain's nameserver change has taken effect at major resolvers.
• Troubleshooting why a site is accessible from some locations but not others.
• Confirming MX or SPF record updates have propagated before testing email.

Examples

Domain: example.com, Record type: A

Cloudflare: 172.66.147.243, 104.20.23.154
Google: 172.66.147.243, 104.20.23.154
Quad9: (same records, one per line)

Domain: gmail.com, Record type: MX

Each resolver lists lines such as:
5 gmail-smtp-in.l.google.com.
10 alt1.gmail-smtp-in.l.google.com.
20 alt2.gmail-smtp-in.l.google.com.

Domain: no-such-host.example.com, Record type: A

Cloudflare: NXDOMAIN / no record
Google: NXDOMAIN / no record
Quad9: NXDOMAIN / no record

Tips

• Lower your TTL to 300 seconds (5 minutes) at least 24 hours before a planned DNS change so propagation completes within minutes, not days.
• After the change is fully propagated, raise TTL back to 3600 or 86400 to reduce DNS query volume and improve cache hit rates.
• If results are still inconsistent after 4 hours, check whether you actually saved the record at your DNS provider — accidental no-saves are common.
• Some ISPs run their own caching resolvers with custom TTL overrides — propagation may take longer at those ISPs than at public resolvers.
• For email delivery testing, also re-check SPF and DKIM with a separate DNS lookup tool to confirm the records resolve correctly, not just propagate.
• Use the NS record type to verify nameserver delegation matches what your registrar shows — mismatches cause hidden propagation issues.

Frequently Asked Questions

Glossary

TTL (Time To Live)

An integer field on each DNS record (in seconds) that tells resolvers how long to cache the response before re-querying. Lower TTL = faster propagation but higher query volume.

Anycast DNS

A routing technique where the same IP (e.g. 1.1.1.1, 8.8.8.8) is announced from many physical data centers globally, and BGP routes each user to the nearest one. Used by major public resolvers for low latency and resilience.

A record

An IPv4 address record — maps a hostname (e.g. www.example.com) to a 32-bit IPv4 address. The most common DNS record type.

AAAA record

An IPv6 address record — maps a hostname to a 128-bit IPv6 address (e.g. 2606:2800:220::ace). Pronounced 'quad-A'.

CNAME record

Canonical Name record — aliases one hostname to another (e.g. www.example.com → example.com). Cannot coexist with other records on the same name.

MX record

Mail Exchange record — specifies the mail server(s) that accept email for a domain, with a priority value for ordering.

TXT record

A free-form text DNS record commonly used for SPF, DKIM, DMARC, domain ownership verification, and other metadata.

NS record

Nameserver record — declares which DNS servers are authoritative for the domain. Set at both the registrar (delegation) and the zone itself.

Recursive resolver

A DNS server that takes a client query and walks the DNS hierarchy (root → TLD → authoritative) to return a final answer, caching responses along the way.