Network Sentinel
Prove zero network calls, live.
Runs entirely in your browser — nothing you enter is uploaded, logged, or tracked.
Network Sentinel hooks every way a web page can talk to the network — fetch, XMLHttpRequest, WebSocket, sendBeacon, EventSource, and the browser's own PerformanceObserver — and counts each outbound request the instant it happens. Watch the live counter sit at zero while you use the page, then hit "Run a self-test" to fire one deliberate request and see the monitor catch it. This is the same proof behind every RVNT tool's promise that nothing you enter ever leaves your browser.
The monitor is instrumenting every outbound channel this page can use. Interact with the tab — click around, switch fields — and watch this stay at zero. If anything ever leaves your browser, it appears below, timestamped.
The PerformanceObserver channel is the independent backstop: it reports resource and navigation entries the browser itself records, catching loads (images, scripts, pings, prefetch) even if they never touched the patched functions. A baseline of this page's own assets is taken on load, so only requests made after you arrive are counted.
Frequently asked questions
How does it know about every request?
It wraps the genuine fetch, XMLHttpRequest, WebSocket, navigator.sendBeacon and EventSource functions (calling the real ones underneath, so the page keeps working) and also attaches a PerformanceObserver to the browser's resource and navigation timing entries. The observer is an independent backstop — it reports loads such as injected images, scripts and prefetches even if they never went through the patched functions.
Why does the counter start at zero if the page itself loaded over the network?
It takes a baseline of this page's own assets the moment it loads, so only requests made after you arrive are counted. That's the honest claim: while you interact with the tool, nothing new should leave — and if it does, you'll see it logged with a timestamp.
What does the self-test prove?
It deliberately fires one real same-origin request (cache-busted so the browser truly hits the network) and tags that row gold. You watch the monitor catch it, then confirm it's the only entry — demonstrating the counter genuinely reacts to outbound traffic rather than always showing zero.
Is anything sent or recorded anywhere?
No — the monitor runs entirely in your browser and the only network call it ever makes is the one you trigger with the self-test button. Nothing is logged to a server, and the request log lives only in the current tab.