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Boulder air right now

GoodAQI 25

Boulder’s five-day smoke forecast shows the current index and the clearest time ahead.

25
AQI now
4.5
PM2.5 · µg/m³
2 cleaner spots within 3 hr drive

Where are you?

Search covers Canada and the United States.

The better move within a 3-hour drive

Dates

Dates follow you into hotel searches. Live inventory is confirmed by the provider.

Vail looks like the better move.69% cleaner air with a verified 2 h 20 min road trip. Rankings balance cleaner air with trip ease.

Every town is also available in the ranked list.
Boulder Clean · PM2.5 0–5 Good · 5–9 Elevated · 9–15 Polluted · 15–35 Unhealthy · 35–55 Severe · 55+
Top pick
Georgetown
Cel-shaded illustration of Georgetown
AQI 7
#1GeorgetownChecking road route

Colorado· Good

Historic mining town near 8,500 feet on I-70 in Clear Creek Canyon, with cool mountain-valley air.

71% cleaner than home — pack the car.

PM2.5 is 1.3 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.3/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.2 µg/m³ less fine-particle pollution than Boulder right now

71% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Leadville
Cel-shaded illustration of Leadville
AQI 7
#2LeadvilleChecking road route

Colorado· Good

North America's highest incorporated city at 10,150 feet, with thin alpine air and historic hotels.

71% cleaner than home — pack the car.

PM2.5 is 1.3 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.3/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.2 µg/m³ less fine-particle pollution than Boulder right now

71% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Dillon
Cel-shaded illustration of Dillon
AQI 8
#3DillonChecking road route

Colorado· Good

Reservoir town in Summit County near 9,100 feet, ringed by peaks with open-water air and resorts.

69% cleaner than home — pack the car.

PM2.5 is 1.4 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.4/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.1 µg/m³ less fine-particle pollution than Boulder right now

69% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Silverthorne
Cel-shaded illustration of Silverthorne
AQI 8
#4SilverthorneChecking road route

Colorado· Good

Summit County outlet town near Lake Dillon, a high-elevation base with condos and mountain air.

69% cleaner than home — pack the car.

PM2.5 is 1.4 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.4/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.1 µg/m³ less fine-particle pollution than Boulder right now

69% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Frisco
Cel-shaded illustration of Frisco
AQI 8
#5FriscoChecking road route

Colorado· Good

Summit County lake town near 9,100 feet on Lake Dillon, with open-water mountain air and abundant lodging.

69% cleaner than home — pack the car.

PM2.5 is 1.4 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.4/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.1 µg/m³ less fine-particle pollution than Boulder right now

69% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Winter Park
Cel-shaded illustration of Winter Park
AQI 9
#6Winter ParkChecking road route

Colorado· Good

Ski town over Berthoud Pass near 9,000 feet, with thin alpine air and a large base of condos and lodges.

About the same air — still smoky.

PM2.5 is 1.6 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.6/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

2.9 µg/m³ less fine-particle pollution than Boulder right now

64% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Granby
Cel-shaded illustration of Granby
AQI 9
#7GranbyChecking road route

Colorado· Good

Middle Park ranching town near Lake Granby and Rocky Mountain National Park, with open-water mountain air.

About the same air — still smoky.

PM2.5 is 1.6 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.6/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

2.9 µg/m³ less fine-particle pollution than Boulder right now

64% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Estes Park
Cel-shaded illustration of Estes Park
AQI 9
#8Estes Park~1 h drive

Colorado· Good

Gateway town to Rocky Mountain National Park near 7,500 feet, where high-elevation air sits well above the Front Range, with lodges and cabins.

About the same air — still smoky.

PM2.5 is 1.7 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.7/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

2.8 µg/m³ less fine-particle pollution than Boulder right now

62% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:12 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Evergreen
Cel-shaded illustration of Evergreen
AQI 18
#9EvergreenChecking road route

Colorado· Good

Foothills mountain town near 7,200 feet west of Denver, ringed by national forest with cooler air.

About the same air — still smoky.

PM2.5 is 3.2 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 3.2/22 × 7 = 1.0 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →
29% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 5:00 p.m. EDT

PM2.5 from the Chatfield Park - 11500 N. Roxborough Park Rd. monitor.

Directions
Still smoky
Aurora
Cel-shaded illustration of Aurora
AQI 19
#10AuroraChecking road route

Colorado· Good

A major Colorado city with broad lodging options and live air-quality readings for comparison when smoke shifts across the region.

About the same air — still smoky.

PM2.5 is 3.5 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 3.5/22 × 7 = 1.1 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →
22% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 5:00 p.m. EDT

PM2.5 from the Denver - NJH - 14th Ave. & Albion St. monitor.

Directions
Still smoky
Denver
Cel-shaded illustration of Denver
AQI 22
#11Denver~40 min drive

Colorado· Good

A major Colorado city with broad lodging options and live air-quality readings for comparison when smoke shifts across the region.

About the same air — still smoky.

PM2.5 is 3.9 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 3.9/22 × 7 = 1.2 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →
13% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 5:00 p.m. EDT

PM2.5 from the Denver - CAMP - 2105 Broadway monitor.

Directions
Still smoky
Nederland
Cel-shaded illustration of Nederland
AQI 25
#12NederlandChecking road route

Colorado· Good

Mountain town near 8,200 feet above Boulder on the Peak to Peak Highway, with cool ridge air.

About the same air — still smoky.

PM2.5 is 4.5 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 4.5/22 × 7 = 1.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →
0% worse airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 5:00 p.m. EDT

PM2.5 from the Boulder - CU - 2102 Athens St. monitor.

Directions
Breckenridge
Cel-shaded illustration of Breckenridge
AQI 8
#13Breckenridge~2 h 10 min drive

Colorado· Good

Historic ski town above 9,600 feet in the Colorado Rockies, where thin alpine air sits far above Denver's haze, with extensive lodging.

69% cleaner than home — pack the car.

PM2.5 is 1.4 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.4/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.1 µg/m³ less fine-particle pollution than Boulder right now

69% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:12 p.m. EDT

PM2.5 is estimated for this town.

Directions
Vail
Cel-shaded illustration of Vail
AQI 8
#14Vail~2 h 20 min drive

Colorado· Good

Purpose-built alpine resort at 8,150 feet in the White River high country, with cool mountain air and a large base of lodges and condos.

69% cleaner than home — pack the car.

PM2.5 is 1.4 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.4/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.1 µg/m³ less fine-particle pollution than Boulder right now

69% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:12 p.m. EDT

PM2.5 is estimated for this town.

Directions
Buena Vista
Cel-shaded illustration of Buena Vista
AQI 8
#15Buena VistaChecking road route

Colorado· Good

Arkansas River town near 7,900 feet ringed by fourteeners, a whitewater base with cool high-country air.

67% cleaner than home — pack the car.

PM2.5 is 1.5 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.5/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3 µg/m³ less fine-particle pollution than Boulder right now

67% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Grand Lake
Cel-shaded illustration of Grand Lake
AQI 9
#16Grand Lake~2 h 35 min drive

Colorado· Good

Village on Colorado's largest natural lake at the west gate of Rocky Mountain National Park near 8,400 feet, with lakeside lodges.

About the same air — still smoky.

PM2.5 is 1.6 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.6/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

2.9 µg/m³ less fine-particle pollution than Boulder right now

64% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:12 p.m. EDT

PM2.5 is estimated for this town.

Directions
Still smoky
Carbondale
Cel-shaded illustration of Carbondale
AQI 9
#17CarbondaleChecking road route

Colorado· Good

Roaring Fork Valley town near 6,200 feet below Mount Sopris, a quieter base than nearby Aspen.

About the same air — still smoky.

PM2.5 is 1.6 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.6/22 × 7 = 0.5 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

2.9 µg/m³ less fine-particle pollution than Boulder right now

64% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Pinedale
Cel-shaded illustration of Pinedale
AQI 3
#18PinedaleChecking road route

Wyoming· Good

Wind River Range gateway near 7,200 feet, a wilderness-trailhead base with cool high-country air.

87% cleaner than home — pack the car.

PM2.5 is 0.6 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 0.6/22 × 7 = 0.2 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.9 µg/m³ less fine-particle pollution than Boulder right now

87% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 4:00 p.m. EDT

PM2.5 from the Pinedale Gaseous monitor.

Directions
Saratoga
Cel-shaded illustration of Saratoga
AQI 7
#19SaratogaChecking road route

Wyoming· Good

North Platte River hot-springs town in the Snowy Range foothills, a remote high-plains lodge base.

73% cleaner than home — pack the car.

PM2.5 is 1.2 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.2/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.3 µg/m³ less fine-particle pollution than Boulder right now

73% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Chama
Cel-shaded illustration of Chama
AQI 7
#20ChamaChecking road route

New Mexico· Good

High-country railroad town near 7,900 feet on the Colorado border, with cool mountain-valley air.

73% cleaner than home — pack the car.

PM2.5 is 1.2 µg/m³ here vs 4.5 back home.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at these levels: 1.2/22 × 7 = 0.4 here; 4.5/22 × 7 = 1.4 at home.A long-term health-risk equivalence, not literal smoking.See how we work it out →

3.3 µg/m³ less fine-particle pollution than Boulder right now

73% cleaner airChecking trip easeChecking nearby staysChecking today's weather

Observed Aug 23, 6:27 p.m. EDT

PM2.5 is estimated for this town.

Directions
Bad week ahead? Check the 7-day outlook — if it won’t clear, book the trip

7-day outlook

Plan the next seven days

Pick a day, or compare the whole week. Weather is forecast; air quality is the latest available reading.

Loading the week…

Finding the nicest days and reachable cities.

Observed Aug 23, 5:00 p.m. EDTLast scan Aug 23, 6:27 p.m. EDT · 49 min ago

Why live rankings? Smoke plumes are patchy and shift with the wind, so no direction is reliably cleaner. This list is recalculated from live PM2.5 every hour — and if everything nearby is smoky, it says so.

How we work this out →

Browse all 200 cities by province & state →

More air-quality pages in Colorado →
Aurora air qualityColorado Springs air qualityDenver air qualityFort Collins air quality
Air quality in nearby cities →
Rapid City air qualityProvo air qualityAlbuquerque air qualitySalt Lake City air qualityOgden air qualityAmarillo air qualityBillings air qualityWichita air qualityLubbock air qualityBozeman air qualityOmaha air qualitySioux Falls air quality

What this means · Boulder

Good

AQI 25

AQI = Air Quality Index

Typical person. Air quality is satisfactory for most outdoor plans.

Kids, seniors, heart or lung conditions. Unusually sensitive people can still enjoy the outdoors.

The AQI on this page follows fine particles (PM2.5). Particles here are 4.5 µg/m³ (Clean), so the headline and the particle scale below tell the same story.

Act two · Fine particles only

Where PM2.5 lands

This bar is smoke and fine particles (PM2.5) only. Left is cleaner air; right is heavier particle pollution. Today's particles sit in Clean.

4.5 µg/m³
Clean · 0Smoky · 40Severe · 80+

Act three · Particle ladder

What each PM2.5 rung feels like

  • 0–3µg/m³Natural. About as clean as outdoor air realistically gets.
  • 3–5µg/m³Clean. Crisp, destination-worthy air.
  • 5–9µg/m³Good. Clean city air; most people will not notice anything today.
  • 9–15µg/m³Elevated. Usually no big deal today; sensitive lungs may notice hard exercise.
  • 15–35µg/m³Polluted. Smoke or traffic pollution is now worth acting on.
  • 35–55µg/m³Unhealthy. Symptoms become more likely, especially with asthma or heart disease.
  • 55+µg/m³Severe. Everyone should reduce exposure and clean the indoor air.

Act four · Felt number

Cigarettes a week

A secondary feel for the particle load only — not a medical claim, and not a substitute for AQI.

1.4/wk

What is PM2.5?

Fine particles about 30× thinner than a human hair — small enough to slip through your lungs and into your bloodstream. We measure them inµg/m³: micrograms of particle mass in a cubic metre of air.

The math

PM2.5 here is 4.5 µg/m³.Berkeley Earth: 22 µg/m³ for 24 h ≈ 1 cigarette.A week at this level: 4.5/22 × 7 = 1.4 cigarettes.A long-term health-risk equivalence, not literal smoking.See how we work it out →
See the full method →