Langues

DNS Checker

Free, no signup. Ask three public resolvers the same DNS question. When their answers differ, you can see the propagation evidence instead of guessing.

Built by Patrick Stox

For PTR, enter either a reverse DNS name or an IPv4 address. Each resolver is queried independently.

Checks run from our server; we fetch the URL you enter and don't keep the results. Queries use Cloudflare, Google, and Quad9 DNS-over-HTTPS. Results are cached briefly (about one minute) so this is not an instant authoritative DNS check. Anonymous run-level outcome counters may be used for aggregate research; URLs, domains, IPs, and identifiers are never included, and no statistic is released below 100 runs.

Feedback
Report a bug

Found something broken in Dns Checker? Let us know what happened — this goes straight to a private triage queue, not a public list.

What will be sent 
 No tool inputs, uploads, pasted source, complete results, query parameters, or URL fragments are attached automatically. You can edit or remove the selected passage above. Browser and anti-abuse metadata is processed for spam prevention. 
  
 
  
 
 
  
 
 
  
 
 
Sample report
Illustrative example — fixed resolver answers
  • Cloudflare: A 192.0.2.10 (TTL 300s)
  • Google: A 192.0.2.10 (TTL 240s)
  • Quad9: A 192.0.2.20 (TTL 300s)
Signal to review: resolver answers differ. This can be propagation, split-horizon behavior, or a resolver issue; it is not automatically a bad zone.
 
 
How to use it
  1. Enter a domain or DNS name and select the record type.
  2. Choose Look up DNS to query Cloudflare, Google, and Quad9 independently.
  3. Compare answer values and TTLs, then review mismatch or resolver-error flags.
  4. Use the copyable zone-file reference for notes only; edit real records at the authoritative DNS provider.
 
 
       
     
     
What the results mean
Matching values across three recursive resolvers are consistency evidence. Different TTLs alone are normal as caches age. A value mismatch means the resolver views differ. A DNS status or network failure belongs only to that resolver and is not converted into a clean answer.
How it works
The browser sends three parallel DNS-over-HTTPS requests through the bounded endpoint. The response preserves each resolver’s status, typed answers, TTLs, authority context, and errors. Deterministic comparison rules flag differing values or unavailable resolvers, explain the selected record and response status in plain language, identify a small curated set of provider-controlled hostnames only when they appear in returned records, and convert observed answers into zone-style text.
Features
  • Eleven common record types including PTR and SRV.
  • Side-by-side Cloudflare, Google, and Quad9 results.
  • Plain-language record and DNS status explanations.
  • Evidence-led delivery and email-service hints from returned hostnames.
  • TTL, resolver status, and propagation flags.
  • Copyable observed-answer reference.
Limitations
These are cached recursive views, not direct authoritative queries, and results are briefly cached by this service. Provider hints cover only a small curated hostname set and do not prove an account is active or reveal an origin. The tool does not trace delegation, edit records, validate DNSSEC chains, test every geographic resolver, or prove the cause of a mismatch.
 
Frequently asked questions
Why do the three resolvers disagree?
Different recursive resolvers can retain old answers until their TTL expires. A mismatch can indicate propagation, split-horizon DNS, or a resolver failure; it is not by itself proof of a misconfiguration.
Does the zone-file export change DNS?
No. It is a copyable representation of observed answers, not an authoritative export and never a write to your DNS provider.
Which DNS record types can I check?
The checker supports A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV, and PTR. PTR accepts an IPv4 address or a reverse-DNS name.
Are these authoritative DNS answers?
No. Cloudflare, Google, and Quad9 are recursive resolvers. Their cached view is useful for propagation checks, but the domain’s authoritative nameservers are the source of record truth.
Next stepHosting Checker — look up the exact spec and expected values.

People also explore
ToolHTTP Header CheckerToolWebsite Down CheckerToolDomain ReportArticleWebsite Hosting Migration SEOArticleEdge SEOArticleCaching for SEO
 
 
 
Feature requests for Dns Checker
 

Upvote what you want most. New ideas can be submitted from the floating Feedback menu;
      requests appear here once approved, and the most-wanted rise to the top.

   
Loading…
  
  ➕ Request a feature   
New requests are reviewed before they appear here.
 
     
  
  
 
 
 
 
    
   
À propos de l’outil
Comparez les réponses DNS d’un domaine auprès de plusieurs résolveurs publics. Examinez les enregistrements A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV et PTR, les différences de propagation et les preuves retournées par chaque service.
Fonctionnalités
  • Résolveurs publics multiples avec comparaison des réponses par type d’enregistrement.
  • Prise en charge des enregistrements A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV et PTR.
  • Vérifications SPF, DMARC, CAA, DNSSEC, NXDOMAIN et SERVFAIL avec preuves lisibles.
  • Import d’origines, de locales, d’alias et de contexte enregistré pour répéter une investigation.
Fonctionnement
Le navigateur envoie les noms et types demandés au service de vérification, qui interroge plusieurs résolveurs publics et renvoie les réponses normalisées. Le calculateur compare les ensembles, met en évidence les divergences et rattache chaque conclusion à une preuve.
Limites
  • Les résolveurs publics et les caches peuvent observer des états différents pendant la propagation ; l’outil ne modifie jamais votre DNS.
  • Les résultats reflètent les réponses publiques au moment de la vérification et ne constituent pas une preuve de disponibilité durable.
Questions fréquentes
Pourquoi deux résolveurs DNS renvoient-ils des réponses différentes ?
La propagation, les TTL, les caches et les chemins de résolution peuvent différer. Comparez les réponses et attendez l’expiration des caches avant de conclure à une panne.
Quels types d’enregistrements puis-je vérifier ?
L’outil couvre A, AAAA, CNAME, MX, TXT, NS, SOA, CAA, SRV et PTR, ainsi que des contrôles SPF, DMARC et DNSSEC.
Le vérificateur modifie-t-il mes enregistrements DNS ?
Non. Il lit uniquement les réponses publiques et ne peut ni publier, ni modifier, ni supprimer un enregistrement.
Que signifie SERVFAIL ?
SERVFAIL indique qu’un résolveur n’a pas pu obtenir une réponse valide, souvent à cause de la délégation, de DNSSEC ou d’un serveur faisant autorité défaillant.