ipcalc, MXToolbox, DNSChecker, it-tools… every tool has its strengths. Here are honest comparisons to help you choose the right tool for your needs — in English and free of charge.
| Need | Reference tool | NetTools FR |
|---|---|---|
| Fast subnetting from the command line | ipcalc (Linux) | Subnet calculator — in the browser, no installation |
| Complete email diagnostics (blacklists, SMTP) | MXToolbox (English) | SPF/DKIM/DMARC validator — in English, free, no account required |
| Global DNS propagation | DNSChecker (English) | DNS response test — 3 resolvers, the essentials without the clutter |
| General-purpose developer toolbox | it-tools.tech | Network-focused: 48 tools for addressing, DNS, Linux and Cisco |
| IPv4 ↔ binary, CIDR conversion | Various sites with ads | Converter + CIDR — with educational explanations |
ipcalc strengths: installed by default on many distributions, perfect over SSH, fast text output.
Its limits: limited to the command line — unusable from a phone, a corporate browser, or to show a calculation to a non-technical colleague. VLSM and VLANs require other tools.
What NetTools FR brings: the same calculations in the browser (IPv4/CIDR, VLSM, VLAN), with detailed results, loadable examples and share links. Ideal for studying or working from any workstation.
MXToolbox strengths: very comprehensive on email — SMTP test, open relay, dozens of blacklists, detailed timings. A reference for email professionals.
Its limits: English-only interface, ads, and some advanced features (monitoring, API) are paid. A lot of noise for a simple “are my emails going to spam?”.
What NetTools FR brings: the essential diagnostics in English — SPF (with the 10-lookup limit), DKIM, DMARC, MX and TXT — in seconds, with no account required. For an in-depth email audit including blacklists, keep MXToolbox as a complement.
DNSChecker strengths: DNS propagation across dozens of global resolvers, an interactive map and all record types.
Its limits: English-only, ads, and a global display that is sometimes overkill for a simple local cache issue.
What NetTools FR brings: a readable DNS response test (local resolver, Cloudflare, Quad9) and complementary tools in English: full lookup, PTR, NS. For detailed worldwide propagation, DNSChecker remains the reference — joining it is on our roadmap.
it-tools strengths: a remarkable open-source project, 80+ developer tools, self-hostable, offline.
Its limits: general-purpose — few server network tools (no ping, no TCP test, no DNS diagnostics), English-only interface, and no educational explanations.
What NetTools FR brings: the network depth that it-tools lacks: ping, TCP test, SSL/TLS, SPF/DKIM/DMARC, WHOIS, not to mention subnetting explained step by step so you can learn.