48 tools, 36 offline
Every tool declares its runtime in the registry. A test asserts the declaration matches what the code actually does, so the offline count cannot quietly become a lie.
NetDash Toolkit
48 network engineering tools. 36 of them never touch the network. The 12 networked tools tell you exactly which hosts they contact before they contact them.
What this is
Section titled “What this is”NetDash Toolkit is a static Next.js app: subnet math, VLSM planning, ACL and VLAN config generation, DNS lookups, TLS inspection, and a pile of developer utilities. There is no backend. The web build is a static export served from a CDN, and the desktop build serves that same export from a loopback HTTP server on 127.0.0.1:17890, which means the docs you are reading work with the network unplugged.
The desktop build also does things a browser physically cannot: real ICMP ping, a system traceroute, and TCP connect scanning. Those pages explain the mechanism rather than hand-waving it.
No backend
output: "export" means there is no server to send your input to. The tools that do leave the
device name their hosts up front.
Honest about limits
A browser cannot send ICMP, cannot read arbitrary response headers cross-origin, and cannot
fetch http:// from an HTTPS page. The docs say so instead of pretending otherwise.
Verifiable builds
Releases carry SLSA Build L3 provenance, GitHub attestations, a CycloneDX SBOM, and SHA-256 checksums. MIT licensed.
Where to go next
Section titled “Where to go next”Quick startOpen a tool, understand the offline badge, save a result.
All 48 toolsEvery tool by category, generated from the app's own registry.
What a browser cannot doWhy ping is an HTTPS round trip, and why a missing header is not an absent header.
What leaves your devicePer-capability data handling, derived from the tool registry.