OneWebDesk
All tools
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Free Web Diagnostic Tools

Free IP · DNS · SSL · email · SEO checks. No sign-up, instant in your browser.

Network / IPDNS / DomainTLS / CertificatesEmailSEO / IndexingOps / SRE

10 tools · no sign-up · 100% free

IP, DNS, SSL/TLS, email, security, SEO and performance checks in one place. Free diagnostic tools for webmasters, developers and operators.

Network / IP

3 tools
CIDR Calculator
Calculate IP range, subnet mask and host count from CIDR notation.
IPv6 Compress / Expand
Convert IPv6 addresses between compressed and expanded forms.
Public / Private IP Checker
Check whether an IP is private, loopback or a reserved range.

DNS / Domain

2 tools
Domain Status Code Decoder
Explain EPP domain status codes like clientTransferProhibited.
DNS Change Impact Checklist
Check risks before changing NS, MX or TXT records.

TLS / Certificates

1 tool
SSL Error Message Decoder
Explain browser SSL errors like ERR_CERT_COMMON_NAME_INVALID.

Email

1 tool
Email Bounce Code Decoder
Explain 4xx/5xx SMTP bounce codes and how to fix them.

SEO / Indexing

2 tools
Meta Title Length Checker
Check title length and how it fits in search results.
Meta Description Length Checker
Check description length and search snippet fit.

Ops / SRE

1 tool
Uptime SLA Calculator
Compute allowed downtime per period for 99%–99.999% SLAs.