How hot is it?
Round 1/10Score 0
Your guess: 5,219 K
Two glows, each at its real temperature, as your eye would see them.
Your guess: 5,219 K
Two glows, each at its real temperature, as your eye would see them.
Your rounds will show up here.
Every glow is a real object at its real temperature: stars, a candle, lamps, lava, lightning. The colors are the explorer's defaults, CIE 1931 blackbody colors at the brightness a dark-adapted eye would see, so a lamp rated 2,700 K looks like a 2,700 K blackbody even though the lamp itself is cool.
Guesses are scored by how far off you are along the slider, not in kelvin. The slider gives most of its length to 2,400–12,000 K, where color changes the most, so missing a candle by 1,000 K costs more than missing Zeta Puppis by 10,000 K. Within 1% of the slider is 100 points; a quarter of the slider away is 0.
In "Which is hotter?" the two get closer together as the rounds go on. Your best score stays on this device.
Explore any temperature to see why the colors come out the way they do.