A speed test that doesn't track you
What this is
Internet Sloth is a speed test. It measures your download speed, upload speed, latency, and jitter. The four numbers that actually tell you whether your connection is working.
No ads. No accounts. No third-party trackers. Free forever. The sloth just wants to know if you're getting what you're paying for.
Your test history stays in your browser, not on our servers. You can chart it, export it to CSV, or run tests on a timer to catch your connection at its worst.
How we're different
- Ookla (Speedtest.net) sells your data. We don't.
- Google's in-page widget has no history. We save yours locally.
How we measure
Transfer tests run through a Cloudflare Worker at the location closest to you, not a server we own, and not one your ISP can host to make their numbers look better.
We open up to 48 parallel streams, scaled to your connection speed, and warm up the connection before timing starts. We then sample throughput every 500 ms. The bottom 25% of samples are discarded to remove TCP ramp-up noise. Fast connections exit early once the result stabilises.
Latency is the median of 3 ping samples. Jitter is the mean absolute difference between consecutive samples (RFC 3550). It captures how much your latency bounces between requests, not just the overall range.
What touches the server
What gets sent
- Your speed results (download, upload, latency, jitter)
- A hashed version of your IP address (SHA-256 hashed, not reversible, never stored raw)
- A random ID generated in your browser. We use it to count how many people run tests and detect site issues. It has no connection to who you are.
What does not happen
- No cookies
- No fingerprinting
- No third-party ad or analytics scripts
- Site analytics use Umami (open-source, self-hosted, no cross-site tracking, no cookies)
That's the whole story.
Run a speed test →Want the technical details? How we measure your speed →
Running an ISP review site or tech blog? There's an embeddable widget.
Questions or bugs: sloth@internetsloth.com