The air,
measured.
A quiet instrument watching the particles drifting through your sky — streamed straight from a real sensor, updated continuously.
Reading the scale
The Air Quality Index translates raw particulate concentration into a single number from 0–500. Here's what each band means for your day.
Air quality poses little to no risk. A fine day to keep the windows open.
Fine for most people. Unusually sensitive individuals may notice mild effects.
Children, older adults, and those with respiratory conditions should reduce prolonged outdoor exertion.
Health effects may begin for the general public. Consider limiting outdoor activity.
Increased risk for everyone. Stay indoors and keep activity light.
Serious risk to the entire population. Remain indoors with air filtration if possible.
Small enough
to disappear.
The sensor behind this page tracks PM2.5 — particles roughly 2.5 microns wide, about thirty times narrower than a human hair. They're light enough to stay suspended in the air for hours and small enough to slip past the body's usual defenses.
Once inhaled, PM2.5 can travel deep into the lungs and, over time, into the bloodstream. That's why short-term averages like the one above matter more than a single instant reading — they show what you're actually breathing over a given stretch of time.