Is 0% humidity possible

No, honestly? 0% humidity just isn't something you'll ever see—not in nature, not even in most labs. Humidity's all about water vapor in the air, and water molecules are basically everywhere. Oceans, soil, your skin, the concrete under your feet, even the plastic in your phone. Getting rid of every last trace? That's a monster of a challenge.

What is relative humidity and why can't it reach zero?

Relative humidity's a weird one. It's the amount of water vapor the air's holding right now compared to what it could hold at that temperature. So 0% would mean absolutely no water vapor at all. But even the driest spots on Earth—think the Atacama Desert or those Antarctic Dry Valleys—rarely dip below 1% or 2% for long. There's always some moisture sneaking in from evaporation, your breath, or just the stuff around you.

Can we create 0% humidity in a laboratory?

In theory, sure. Scientists use desiccants like silica gel or molecular sieves, or they heat air to crazy temperatures. But hitting and keeping exactly 0%? Basically impossible. Here's why:

• Water molecules cling to surfaces and slowly escape back into the air.
• Every seal and container has microscopic leaks that let moisture creep in.
• Even the best drying systems leave behind trace amounts—like, really tiny amounts.

Labs can get down to 0.001% relative humidity (10 parts per million of water), but that's not true zero. For most of us, those "ultra-dry" conditions are close enough.

What would happen if humidity reached 0%?

If you somehow managed to get a spot to 0% humidity, things would get ugly fast:

• Your skin and eyes, nose, throat—all that stuff—would dry out like crazy. Extreme discomfort, maybe even cracking.
• Wood furniture, paper, anything organic? It'd warp, crack, or turn brittle as it loses every bit of moisture.
• Static electricity would go nuts. Dry air can't dissipate charges, so you'd be zapping everything.
• Electronics? Static discharge could fry them.

Data table: Humidity levels in extreme environments

Is 0% humidity possible in space or on other planets?

Out in the vacuum of space, there's no atmosphere to hold water vapor, so relative humidity doesn't really mean anything. But inside a spacecraft, they keep it between 40-60% for astronaut comfort. Mars? Thin, cold atmosphere, but there's still trace water vapor—relative humidity can hit 100% at night (frost forms) and drop near 0% during the day. Even there, it never actually reaches zero because water's in the soil and air.

Checklist: How to achieve extremely low humidity at home

• Get a good dehumidifier and a hygrometer.
• Seal up windows, doors, vents—keep outside moisture out.
• Throw desiccant packs (silica gel) in enclosed spaces.
• Stop doing stuff that makes moisture, like cooking or showering.
• Use a calibrated humidity sensor to keep track.

Do all that, and you'll be lucky to hit 10-15% RH. Not 0%.

Frequently Asked Questions