Domains & DNS
Check records, signatures and spellings – and find the right domain.
- DNS lookupShow all DNS records of a domain: A, AAAA, MX, TXT, NS, SOA, CAA and more – even directly from the authoritative name server.
- DNSSEC checkChecks whether a domain is signed with DNSSEC and whether the chain of trust from the extension down to the zone is intact.
- Punycode converterConverts domains with umlauts and special characters to punycode (xn--) and back – with a warning about confusable characters.
- Domain search & WhoisIs your desired domain available? Live RDAP and Whois lookup directly at the registries.
- Domain valuationWhat is a domain worth? An estimate based on length, extension, age, backlinks and demand.
- TLD wikiEvery domain extension explained – registration rules as published by IANA, ICANN and the registry.
Email, web & network
Mail protection, certificates, headers and reachability at a glance.
- SPF, DKIM & DMARCShows how well a domain is protected against forged senders: SPF, DKIM, DMARC plus MTA-STS, TLS-RPT and BIMI.
- SMTP checkChecks whether a domain’s mail servers are reachable and encrypt securely – and optionally whether a mailbox accepts mail. Without sending an email.
- SSL certificateValidity, expiry date, issuer, names and certificate chain of an HTTPS website at a glance.
- HTTP headersFollows every redirect of a URL and rates the security headers of the final page.
- PingIs a server reachable and how fast does it respond? Four measurements with minimum, average and packet loss.
- TracerouteShows the path data packets take from our data centre to the target – hop by hop.
What are the tools for?
Anyone who looks after domains, mail servers or websites keeps needing the same quick checks: is the DNS record live yet? Does the mail server accept mail? Is the certificate about to expire? The tools answer these questions in your browser – no command line, nothing to install.
The tools are free and ad-free. To keep them fast for everyone and to prevent misuse, each tool has an allowance of 20 checks per day.
Frequently asked questions
Do the tools cost anything?
No. The tools are a free service of 1blu business GmbH. There is no sign-up and no advertising.
Why are the checks limited?
Every check opens real connections to other people’s servers. The limit of 20 checks per tool per day protects those servers and prevents the tools from being used for bulk queries or attacks.
What happens to what I enter?
Your input is only used for the check in question and is not stored. For the daily limit, we only keep a counter under an encrypted identifier that changes daily – not your IP address. These counters are deleted after two days at most.
Domains and DNS in good hands
1blu business GmbH looks after domains, DNS and mail servers for companies, agencies and resellers – with dedicated contacts instead of a call centre.