How fast is mit.edu?
Where the time went
"Doc rate" is the transfer rate of this one document from our vantage, it reflects the server and path, not your bandwidth.
Report card
| Check | Measured | Grade |
|---|---|---|
| Time to first byte | 48 ms | A |
| Document transfer size | 11 KB (gzip) | A |
| Compression | gzip · text/html | B |
| Redirects | 302 → 200 | B |
| HTTP/2 | not supported | − |
| Cache-Control | public, max-age=2201, s-maxage=3600 |
Your connection to us
This panel runs in your browser and measures the path between your device and our edge, latency, jitter, and a rough download estimate. It cannot measure your path to any other site, browsers don't allow that, so use it as the "is it me" half of the diagnosis: if the site's server tests fast here but everything feels slow, your connection is the suspect.
The download number is an estimate from a single 4 MB burst, enough to tell "broadband fine" from "something is wrong", not a substitute for a full bandwidth test. Nothing about your connection is stored.
How we grade
| Grade | Time to first byte | Document transfer size | Redirect hops | Compression |
|---|---|---|---|---|
| A | ≤ 200 ms | ≤ 100 KB | 0 | brotli (or non-text) |
| B | ≤ 400 ms | ≤ 300 KB | 1 | gzip / deflate |
| C | ≤ 800 ms | ≤ 1 MB | 2 | - |
| D | ≤ 1500 ms | ≤ 3 MB | 3+ | - |
| F | worse | worse | - | uncompressed text |
Overall letter = weighted average (first byte counts double), nudged up a third of a grade when the host speaks HTTP/2 and down when it doesn't.
Slow today can be down tomorrow. A free monitor probes mit.edu every 5 minutes with 4 probe methods and emails you when it stops answering, and the live check page has current status and history.