ELI5: What does a fabric's Q-Max score actually measure?

A fabric's Q-Max score measures how much warmth it steals from your skin the very second you touch it, telling you how cold it instantly feels.

Imagine it is a hot summer day and you walk barefoot into the kitchen. If you step on a fluffy rug, it feels warm and normal. But if you step onto smooth tile, your feet instantly say, "Whoa, that’s cold!"

The tile is not actually colder than the rug—both have been sitting in the same room. The difference is that the tile is an expert at snatching heat away from your feet really fast. A Q-Max score is just a number that measures how good a fabric is at playing that exact same heat-stealing trick.

When scientists test this in a lab, here is what they do:

• They warm up a metal plate so it is as warm as human skin.
• They drop that warm plate onto the fabric.
• They measure the biggest, fastest rush of heat flowing into the fabric at that exact split second.

• Around 0.2: This is the baseline. You will notice a very gentle, mild coolness.
• 0.3 to 0.4: This is noticeably cool to the touch, like flipping your pillow over to the "cool side."
• 0.4 and above: This feels instantly, delightfully icy, which is great for hot sleepers or sticky summer nights.