Start here
Getting started
SubnetSlinger runs on your machine. The free tier — nine tools — needs no account, and nothing about your network ever leaves your computer. Here's the whole path from install to your first result, going Pro, and keeping your work safe.
Install it
On Windows, install from the Microsoft Store — free download, and it stays free for the nine-tool tier with no sign-up. macOS, Linux, and the phone companion apps are on the way.
First launch — the Home dashboard
Home shows your machine's network at a glance: hostname, local IPs, gateway, DNS servers, and a live uplink check. The public-IP panel is click-to-load — nothing leaves your machine until you press it. The left rail lists every tool; the search box filters by name (try ping, mac, cert).
Run your first check — Ping
Open Ping. It opens pre-filled with your default gateway — "is my gateway up?" is the usual first check, and it answers even on an isolated lab network with no internet. Press Enter (or the Run button). Type any host or IP over it to test something else.
Read the result
Color and icon mean the same thing everywhere, and there's always a label so you never rely on color alone: green / ✓ = good, amber / ⚠ = degraded, red / ✕ = failed. Low, steady RTT is healthy; 100% loss means down, unreachable, or filtering ICMP. See Reading results for the full rundown.
Explore the free tools
Nine tools are free forever: Ping, Trace, Path ping, Ports, DNS, Subnet calculator, ARP table, MAC / OUI lookup, and Discovery. Most are passive and safe to run anywhere — read Can these tools cause harm? before you scan or SSH to gear you don't own.
Go Pro (optional)
Pro unlocks the whole corral — packet capture, topology, drift, the AI Deputy and Posse, and more. Start a 30-day trial or buy ($499, once) from inside the app. You sign in with your email; we send a one-time code (not a password), and that's the only personal data we hold. Buying opens Stripe in your browser — no card field lives in the app. Full detail: Your account, your license, and your data.
Back up your work
Your data lives on your machine and only there — there's no cloud sync. Use Back up & restore (File menu) to save your inventory, incidents, runbooks, saved maps, watch lists, saved hosts, custom themes, and activity log to one file you can move to a new machine. See Back up & restore your work.
Troubleshooting
The questions we hear most on a first run. We'll grow this as more come in.
- A public site (like google.com) times out, but my local IPs reply.
- That usually means the network has no internet uplink yet — not a broken ping. Local replies with a public host timing out is the tell. Also, some networks filter ICMP to public IPv4 (e.g. 8.8.8.8) even when the internet works — try a name, or flip the IPv4/IPv6 toggle.
- My sign-in email has a code, not a link — and I can't find it.
- That's expected: we email an 8-digit one-time code, not a magic link, so there's no password of yours to reuse. Check spam/junk; the code is time-limited, so request a fresh one if it expired.
- A port scan is slow or shows everything filtered.
- A host firewall silently dropping probes looks like 'filtered' and slows the scan. Scan gear you own and expect to reach. Scanning hosts or networks you don't own or aren't authorized to test can violate policy or law.
- The AI Deputy / Posse won't respond.
- AI is optional and off by default. Either pick a local model via Ollama (nothing leaves your machine), or choose the cloud provider and supply your own Anthropic key. No key (or no Ollama running) means no AI answer. See the Deputy and Ollama articles.
- I copied vault.json to a new machine and it won't open.
- That's deliberate. The Vault is sealed to the Windows user on the machine it was created on — a copied file won't open even with the right passphrase, so a stolen copy is useless. Set your secrets up again on the new machine.
- I signed in on a new computer and my data is gone.
- Your license follows your account; your data does not — the account never held it. Bring your work across with Back up & restore (step 7). Sign in and Pro turns back on; import your backup to restore your inventory, maps, and the rest.