Anonymize IP Addresses in Text
Paste log lines below — any IPv4 or IPv6 address found will have its identifying portion masked. Everything else (timestamps, paths, ports) is left untouched.
Mask IPs in Log Files • Subnet Calculator • 100% Local
Paste log lines below — any IPv4 or IPv6 address found will have its identifying portion masked. Everything else (timestamps, paths, ports) is left untouched.
Many organizations pseudonymize IP addresses before storing them in logs or analytics, since a full IP address is often considered personal data under privacy regulations like GDPR. This tool follows a widely used technical convention for doing that (the same approach long used by Google Analytics' IP anonymization feature): for IPv4, the last octet is zeroed out (e.g. 192.168.1.123 → 192.168.1.0); for IPv6, the last 80 bits are zeroed out, keeping only the first 48 bits (e.g. 2001:db8:85a3::8a2e:370:7334 → 2001:db8:85a3::), since IPv6 addresses carry much more identifying detail per address than IPv4.
This tool provides a technical masking capability, not legal advice. Whether this level of masking is sufficient for your specific situation depends on factors this tool has no way to know — your jurisdiction, what else you store alongside the IP, your retention policy, and more. Consult your organization's legal or data protection guidance for anything beyond the technical masking itself.
The Subnet Calculator is a standard IPv4 networking helper: give it an IP and a CIDR prefix length, and it works out the network address, broadcast address, usable host range, and total host count for that subnet — useful for planning network segments or just double-checking your math.
Everything runs locally in your browser. Log content, IP addresses, and messages are never transmitted anywhere.