Contact Us
We are a small independent team building free network utilities for sysadmins, network engineers, developers, and IT professionals. We read every message we receive.
The best way to reach us is by email: [email protected]
We aim to respond to all messages within 2 business days. For urgent issues, please write "Urgent" in the subject line.
Bug Reports
If a tool is producing incorrect results, please include:
- Tool name — e.g., "IPv4 Subnet Calculator" or "DNS Record Lookup"
- Browser and version — e.g., "Chrome 124 on Ubuntu 22.04"
- Input that caused the issue — the IP address, CIDR, domain name, or other value you entered
- Expected result vs. actual result — what you expected and what the tool showed instead
- Reference — if relevant, the RFC or authoritative source that defines the expected behavior
Feature Requests
Is there a network analysis or calculation tool you use regularly that we do not yet cover? We welcome requests. Please describe the specific task and your use case — whether it is for home lab work, enterprise network planning, cloud infrastructure, or security research. Client-side tools that do not require server infrastructure are our priority.
Business Inquiries
For advertising partnerships, content collaborations, or other business inquiries, please email [email protected] with "Business Inquiry" in the subject line.
About This Site
Network Tools Online is an independent project. We are not affiliated with any networking hardware vendor, cloud provider, or ISP. Our goal is to provide accurate, reliable network utilities that are free to use without registration, subscriptions, or sending your network configuration data to a third-party server.