Best Free Networking Tools Online (2026)

Whether you're debugging DNS issues, testing APIs, or calculating subnet ranges, having the right networking tools can save hours of frustration. But many popular platforms hide features behind paywalls or require account creation. We've compared the top networking tools to help you find the right option for your workflow.

Feature Fixie Networking Tools MXToolbox Postman Hoppscotch
Price Free forever Free (limited) / $129-399/mo Free (1 user) / $14/user/mo Free & open source
Signup Required No Yes (for advanced features) Yes Optional
Privacy / Data Handling No data stored Account-based storage Cloud-synced collections Self-hostable or cloud
DNS Lookup Yes, unlimited Yes (comprehensive suite) No No
Subnet Calculator Yes, unlimited Yes No No
API Testing Basic (request builder) No Yes (industry-standard) Yes (full-featured)
Request Collections No N/A Yes (25 runs/mo free) Yes, unlimited
Team Collaboration No Yes (paid plans) Yes (paid only) Yes (shared workspaces)
Blacklist Monitoring No Yes (core feature) No No
Email Diagnostics No Yes (DMARC, SPF, DKIM) No No
Protocol Support HTTP/HTTPS only SMTP, DNS, HTTP REST, GraphQL, WebSocket, gRPC REST, GraphQL, WebSocket, MQTT, SSE
Cron Expression Builder Yes, visual builder No No No

Our Verdict

The right networking tool depends entirely on what you're trying to accomplish. MXToolbox is the industry leader for email deliverability and DNS diagnostics - if you manage email infrastructure professionally, its blacklist monitoring and DMARC testing are unmatched (though full features require a paid plan starting at $129/month).

For API testing, Postman remains the gold standard for professional development teams, offering collections, environments, mock servers, and comprehensive testing capabilities. However, the free plan limits teams, pushing users toward the $14/user/month paid plan. Hoppscotch provides an excellent open-source alternative with unlimited team collaboration, support for REST, GraphQL, WebSocket, MQTT, and more - all completely free.

Fixie's networking tools excel at instant, no-signup access to common tasks: DNS lookups, subnet calculations, quick API requests, and cron expression building. You won't get saved collections, team workspaces, or email monitoring, but for quick diagnostic work or learning purposes, it offers a clean, privacy-first experience with no account barriers.

Frequently Asked Questions

Which networking tool is best for DNS troubleshooting?
MXToolbox is the most comprehensive for DNS diagnostics, offering lookups, blacklist checking, and email-specific DNS records (SPF, DKIM, DMARC). Fixie offers simple DNS lookups with no signup required, which is great for quick checks.
Is Postman still free for API testing?
Postman's free plan is limited to 1 user with 25 collection runs per month. Teams must upgrade to the paid Team plan at $14 per user per month. For free team collaboration, Hoppscotch is an excellent open-source alternative.
Do I need an account to use these tools?
Fixie requires no signup - all tools work instantly in your browser. MXToolbox requires an account for advanced features. Postman requires an account for all features. Hoppscotch can be used without an account via the web version.
Which tool is best for learning and experimentation?
Fixie is ideal for quick experiments and learning - no signup friction means you can test DNS queries, subnet calculations, and API requests immediately. Hoppscotch is also excellent for learning API testing with its intuitive interface.
What happens to my API requests and data?
Fixie doesn't store your requests or responses. Postman stores collections in your cloud account. Hoppscotch can be self-hosted for complete privacy control. MXToolbox stores diagnostic history in your account.

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