City report · Massachusetts, United States
Boston Air quality today
Air quality in Boston currently reads AQI 18 (Good): Air quality is satisfactory for everyone.
Air quality right now
AQI 18
Good
- PM2.5, fine particles (µg/m³)
- 3.3
- tree cover
- 12.3%
- trees in this area
- 26.6K
- more trees needed
- 38.3K
Measured across a 1.2 mi (2 km) radius around Downtown, Boston, MA, USA (4.9 sq mi), from a satellite image of Sep 15, 2026. Lower AQI is better: 0–50 is Good, above 300 is Hazardous.
Boston · AQI 18 (Good)
Boston's tree count comes to 26,624 trees across 3.3 sq mi (8.66 km²) of land, 18 points below the 30% tree-cover level considered healthy for this area, so roughly 38,313 more trees would close the gap.
Air quality detail
Air quality in Boston today: AQI 18, Good
Main pollutant: PM2.5 · Observed Nov 11, 09:00 local time via OpenAQ ground stations, US EPA index. Values in µg/m³.
Ground station · Boston - Von Hillern, 2.3 mi (3.7 km) away · median of 4 stations
Health signal
Air quality is satisfactory for everyone.
PM2.5
3.3
PM10
4.0
NO₂
22.6
O₃
33.4
SO₂
0.8
CO
114.6
Data: OpenAQ · AirNow
- Outdoor exercise
- A good day to be active outside
- Windows
- Open them to air the house
- Mask
- Not needed
- Air purifier
- Not needed
Over the last 7 days, the CAMS air-quality model put Boston's daily AQI at 33 on average, from 23 on Nov 6 to an hourly peak of 61 on Nov 4.
Where Boston stands: the most polluted cities in the world right now · the cleanest
Tree cover detail
Tree cover in Boston: Critically low
12.3% tree cover against a 30% healthy-neighborhood target, across 3.3 sq mi (8.66 km²) of land.
Trees in this area
26,624
Target trees
64,937
More trees needed
38,313
CO₂ if planted / yr
842.9 t
Deforestation · 2001–2025
How much forest has Boston lost?
Since 2001, the area within 10 km of Boston has lost about 161 acres (65 hectares) of forest (about 120 football fields): 2% of the forest it had in 2000. Most of it (83%) was deforestation, forest cleared for good, mainly for towns and roads.
2017: satellite photo from July 2017 of a 5 × 5 km area in the city center.
- Forest lost since 2001
- 161 acres (65 ha)about 120 football fields
- Share of its forest
- 2%of what there was in 2000
- Cleared for good
- 133 acres (54 ha)deforestation: turned into farms, mines or towns
The worst year was 2017, when about 20 acres (8 hectares) of forest were lost.
Acres of forest lost each year
Show the figures as a table
| Year | Cleared for good | Can grow back | Total |
|---|---|---|---|
| 2001 | 6 acres (3 ha) | under 1 ha | 8 acres (3 ha) |
| 2002 | 5 acres (2 ha) | under 1 ha | 5 acres (2 ha) |
| 2003 | under 1 ha | under 1 ha | under 1 ha |
| 2004 | 3 acres (1 ha) | under 1 ha | 4 acres (2 ha) |
| 2005 | 3 acres (1 ha) | under 1 ha | 4 acres (2 ha) |
| 2006 | 2 acres (1 ha) | 3 acres (1 ha) | 5 acres (2 ha) |
| 2007 | 8 acres (3 ha) | under 1 ha | 10 acres (4 ha) |
| 2008 | 2 acres (1 ha) | under 1 ha | 4 acres (2 ha) |
| 2009 | 2 acres (1 ha) | under 1 ha | 3 acres (1 ha) |
| 2010 | 3 acres (1 ha) | under 1 ha | 5 acres (2 ha) |
| 2011 | under 1 ha | under 1 ha | under 1 ha |
| 2012 | 9 acres (4 ha) | under 1 ha | 10 acres (4 ha) |
| 2013 | 3 acres (1 ha) | under 1 ha | 3 acres (1 ha) |
| 2014 | 7 acres (3 ha) | under 1 ha | 7 acres (3 ha) |
| 2015 | 10 acres (4 ha) | under 1 ha | 10 acres (4 ha) |
| 2016 | 7 acres (3 ha) | under 1 ha | 8 acres (3 ha) |
| 2017 | 18 acres (7 ha) | under 1 ha | 20 acres (8 ha) |
| 2018 | 3 acres (1 ha) | under 1 ha | 4 acres (2 ha) |
| 2019 | 11 acres (5 ha) | under 1 ha | 12 acres (5 ha) |
| 2020 | 7 acres (3 ha) | under 1 ha | 7 acres (3 ha) |
| 2021 | 6 acres (3 ha) | under 1 ha | 6 acres (3 ha) |
| 2022 | 6 acres (3 ha) | under 1 ha | 7 acres (3 ha) |
| 2023 | 4 acres (2 ha) | under 1 ha | 5 acres (2 ha) |
| 2024 | under 1 ha | under 1 ha | under 1 ha |
| 2025 | under 1 ha | 4 acres (2 ha) | 4 acres (2 ha) |
What is causing deforestation around Boston?
- Towns and roadscleared for good83% · 133 acres (54 ha)
- Unknown causescause unknown17% · 27 acres (11 ha)
Causes for 2025 are estimates, based on what caused forest loss in the same places up to 2024.
Forest gained and lost, 2000–2020
- Forest in 2000
- 16,200 acres (6,550 ha)
- Forest in 2020
- 16,200 acres (6,560 ha)
- Overall change
- +7 acres (3 ha)more forest than in 2000
Comparing satellite maps from 2000 and 2020, the forest around Boston stayed about the same size, at about 16,200 acres (6,560 hectares): new forest grew on about 287 acres (116 hectares), and about 277 acres (112 hectares) were lost.
These 2000 and 2020 maps, from the University of Maryland, count any land with trees taller than 5 m as forest, including plantations and orchards. Forest that was cut or burned and had grown back by 2020 counts in both years, so the loss here is smaller than the yearly figures.
These figures cover everything within 10 km of the city center, a wider area than the report above, because forest is usually lost at a city's edges.
Source: Hansen/UMD/Google/USGS/NASA, Global Forest Change (GFC-2025-v1.13); causes: WRI/Google DeepMind drivers of forest loss; both CC BY 4.0, summed by Airleaf for each area. Forest gained and lost 2000–2020: Potapov et al. 2022, UMD GLAD Global Land Cover and Land Use Change, CC BY 4.0. Images: contains modified Copernicus Sentinel data. How it's measured
In the same region
Measured cities near Boston
Same 2 km radius, same index — so they compare directly.
- Lowell37.1 km
United States
- Tree cover
- 31%
- Air quality
- 19
- Worcester62.0 km
United States
- Tree cover
- 27%
- Air quality
- 21
- Providence66.2 km
United States
- Tree cover
- 25%
- Air quality
- 31
- Manchester77.9 km
United States
- Tree cover
- 34%
- Air quality
- 20
- New Bedford81.2 km
United States
- Tree cover
- 19%
- Air quality
- 24
- Springfield129.2 km
United States
- Tree cover
- 31%
- Air quality
- 12
Build your own
Compare Boston with anywhere
This place
Boston
Use this data
Put Boston's numbers on your site
Free to embed. Updates itself as the measurement refreshes.
Frequently asked
Questions about Boston
What is the air quality (AQI) in Boston right now?
The latest reading for Boston shows an AQI of 18 (Good), measured Nov 11, 09:00 local time by 4 ground monitoring stations via OpenAQ (the median of their readings; the nearest is Boston - Von Hillern, 2.3 mi (3.7 km) away). The main pollutant is PM2.5. Air quality is satisfactory for everyone.
Is it safe to exercise outside in Boston today?
At AQI 18 (Good): a good day to be active outside. Windows: open them to air the house. Masks: not needed. The reading changes through the day, so check again before a long run or ride.
What has the air quality in Boston been like this week?
Over the last 7 days, the CAMS air-quality model put Boston's daily AQI at 33 on average, from 23 on Nov 6 to an hourly peak of 61 on Nov 4. No day averaged above 100, the level where the air turns unhealthy for sensitive groups.
How much forest has the area around Boston lost since 2001?
Since 2001, the area within 10 km of Boston has lost about 161 acres (65 hectares) of forest (about 120 football fields): 2% of the forest it had in 2000. Most of it (83%) was deforestation, forest cleared for good, mainly for towns and roads. Comparing satellite maps from 2000 and 2020, the forest around Boston stayed about the same size, at about 16,200 acres (6,560 hectares): new forest grew on about 287 acres (116 hectares), and about 277 acres (112 hectares) were lost.
What is the tree count in Boston?
Boston has an estimated 26,624 trees across the 3.3 sq mi (8.66 km²) of land measured — 12.3% tree cover, 18 percentage points short of the 30% tree-cover target set for this area.
How many more trees does Boston need?
Boston needs roughly 38,313 more trees to close a 18-point shortfall against its 30% tree-cover target — about 842.9 t of extra CO₂ absorbed per year once grown.
How are Boston's air quality and tree cover measured?
Air quality is measured by ground monitoring stations near Downtown, via OpenAQ; the 7-day trend is the Open-Meteo / CAMS model's estimate. Tree cover is measured from Sentinel-2 L2A (ESA Copernicus) via Earth Search satellite imagery at 10 m detail across a 1.2 mi (2 km) radius around Downtown; the tree count is an estimate derived from that cover.
See your own area
What does your neighborhood look like?
Pick any point and radius to get the same air-quality and tree-cover breakdown.
Check my address