One mystery IP address answered pings from five cities. You get the five round-trip times and nothing else, and your job is to drop a pin where you think the address is. The first attempt is played with the times alone. Then the map draws a ring around each city — the furthest the answer can be, at the speed of light in fibre — and the second attempt is played with those rings as clues. Your score is the great-circle distance from your best pin to the truth.
These round-trip times are a model, not measurements. Nothing was pinged. Each time is the great-circle distance from the probe city to the answer, divided by the speed of light in fibre (200,000 km/s) and multiplied by a routing-inefficiency factor of 1.3–2.0, plus 0–3 ms of jitter. The factor and the jitter are fixed by hashes of the day and the address, so everybody gets the same puzzle — but a real ping would come out different, and that is the honest version of what this page is.
Click the map to place your pin; click again to move it.
Click the map to place your pin.
| Probe city | Round trip | Max. range |
|---|---|---|
| Frankfurt, Germany 50.1109, 8.6821 |
136 ms | 13,600 km |
| New York, United States 40.7128, -74.0060 |
110 ms | 11,000 km |
| Tokyo, Japan 35.6762, 139.6503 |
273 ms | 27,300 km |
| São Paulo, Brazil -23.5505, -46.6333 |
8 ms | 800 km |
| Sydney, Australia -33.8688, 151.2093 |
220 ms | 22,000 km |
A signal cannot travel faster than light in fibre, so a round trip of t milliseconds means the answer is at most t / 2 × 200 km away — 100 km for every millisecond of round trip. That is a ceiling, never a fix: one ring on its own leaves most of a hemisphere, and it is only where all five overlap that the answer narrows down. The model's routing factor makes every real path longer than the straight line, so the answer sits inside each ring rather than exactly on it.
The address, the city and the network in the reveal are the same data the rest of the site uses: see a real traceroute on a globe for what a measurement actually looks like, or the network tools. The IP page for the answer is 146.164.1.1.
The tool behind this mechanic: Traceroute on a globe
Prefer countries? There is the daily IP puzzle. Prefer
networks? There is the daily network puzzle, and the
IP passport keeps your stamps. Like this one,
/ping.htm?p=1, ?p=2, ?p=3 … are endless
practice puzzles with a different address each: same rules, no daily number.
This page is in daily mode for 2026-10-23. The daily puzzle is the same for everyone on a given UTC day; a practice puzzle is the same for everyone who asks for the same number.