About This One
The Boiling Frog takes its name from an old story about a frog that will not jump out of water heated slowly enough. The frog part is not true: a frog that can move will try to get out as the water warms, and the one in this pot does exactly that. The part about people holds up much better.
A temperature climbs from 20 to 95 degrees over ninety seconds, visibly, the whole time. Four times, at moments you cannot predict, the display is covered and you are asked how far it rose since the last check. From the second checkpoint on, you are also asked whether it was rising faster or slower than before, because each run secretly follows one of four different curves.
At the end, your estimates are stacked into the curve you thought you were watching and drawn over the real one. The gap between the two lines is the whole point.
The Four Curves
- Steady: the same number of degrees every second.
- Speeding up: slow at first, racing by the end.
- Slowing down: fast at first, crawling by the end.
- Stop-start: three surges, with near-flat stretches between them.
All four start at 20°C and finish at 95°C, so only the shape differs. Your next run always picks a different curve from the last one.
How To Play
- Press Turn on the heat. Watch the number as closely or as loosely as you like.
- When the pot is covered, drag the slider or tap plus and minus to say how many degrees it rose since the last checkpoint.
- From the second checkpoint, also say whether that stretch was faster, slower or about the same as the one before.
- After four checkpoints the heat finishes its run and you see your curve against the real one.
Why This Exists
Most perception tests hide something from you. This one does not. The number is on screen, rising, for the whole ninety seconds, and yet almost nobody can say how much it moved in the last twenty. Watching is not the same as tracking.
That gap matters well beyond a pot of water. Prices, waistlines, workloads and climates all change slowly enough to feel like they are standing still, right up until someone shows you the chart.
Frequently Asked Questions
What is The Boiling Frog?
A free test of how well you track slow change. A temperature rises in full view from 20 to 95 degrees over ninety seconds. At four surprise checkpoints the display is covered and you estimate how many degrees it rose since the last check and, from the second checkpoint on, whether it was rising faster or slower than before. At the end your estimates are drawn against the real curve.
Is the frog part true?
No. The story that a frog will sit in slowly heated water until it boils is a myth. Nineteenth-century experiments are often cited for it, but modern biologists point out that a frog able to move will try to get out as the water warms. The frog in this game leaves the pot when it gets uncomfortable. The name survives as a metaphor about people, which is what this game actually tests.
Does the temperature always rise the same way?
No. Each run secretly follows one of four curves: steady, speeding up, slowing down, or stop-start, which rises in surges with flat stretches between them. All four start at 20 degrees and end at 95, so only the shape differs. The curve is revealed at the end, and the next run picks a different one.
How is the score worked out?
Each of the four estimates is worth up to 25 points, losing two and a half points for every degree you are off. That makes 100 points for the estimates, which count for three quarters of the score. The three faster-or-slower questions count for the final quarter. Your best score is kept in your browser.
Is this based on real research?
Loosely. Psychologists have shown that people often miss changes that happen gradually, even while looking straight at them, an effect sometimes called gradual change blindness. This game is an informal illustration of the same tendency applied to a number, not a scientific instrument.
Does it work on mobile?
Yes. Everything is built for touch: you set each estimate by dragging a slider or tapping the plus and minus buttons, and the faster or slower answers are large buttons. Sound is optional and off by default.
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