Air quality comparison · United States, 73.3 mi (118 km) apart
Austin vs San Antonio Air quality index (AQI) today
Austin has cleaner air than San Antonio right now: AQI 26 (Good) against 33 (Good).
Both sit in the same EPA band, so the health advice is the same for each today. Over the past 7 days, on modeled daily averages, Austin averaged AQI 43 against 47, and it was the cleaner of the two on 4 of those days. Austin has lost more forest since 2001. Austin has more tree cover.
United States
AQI 26
Good
Cleaner right now
- PM2.5
- 4.6 µg/m³
- Main pollutant
- PM2.5
- Source
- Ground station
- Reading
- Nov 11, 09:00 local
United States
AQI 33
Good
Cleaner right now
- PM2.5
- 6 µg/m³
- Main pollutant
- PM2.5
- Source
- Ground station
- Reading
- Nov 11, 09:00 local
Updated . Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous. Measured by Airleaf.
Austin26San Antonio33
Head to head
Austin vs San Antonio at a glance
Austin is ahead on 5 of 6 measures, and San Antonio on 1. The better figure in each row is marked.
| Austin | San Antonio | |
|---|---|---|
| Air quality nowUS AQI. Lower is better. | 26 (better) | 33 |
| PM2.5Fine particles, µg/m³. | 4.6 (better) | 6 |
| Past week's averageUS AQI, 7 days. | 43 (better) | 47 |
| Forest lost since 2001Within 10 km of the center. | 2,170 acres (876 ha) | 447 acres (181 ha) (better) |
| Tree coverWithin 1.2 mi (2 km) of the center. | 28.2% (better) | 14.7% |
| Trees still neededTo reach a healthy canopy. | 5.5K (better) | 48.1K |
Air quality today
What is the air like in Austin and San Antonio right now?
Austin has cleaner air than San Antonio right now: AQI 26 (Good) against 33 (Good). PM2.5 is setting the index in both.
Both readings come from nearby ground stations.
AustinSan Antonio
Concentrations at the same moment as the index above, for the pollutants both places report. Lower is better. The dark marks on the PM2.5 and PM10 rows show the WHO's 24-hour guidelines (15 and 45 µg/m³).
The past week
Which had cleaner air over the past 7 days?
Over the past 7 days, on modeled daily averages, Austin averaged AQI 43 against 47, and it was the cleaner of the two on 4 of those days. A single reading can catch a city on a bad afternoon; the week says whether it was the weather or the place.
- Cleaner days
- Austin4San Antonio3
- Average AQI
- Austin43San Antonio47
- Worst day, AQI
- Austin67San Antonio62
The daily numbers (7 days)
| Day | Austin | San Antonio |
|---|---|---|
| Nov 4 | 21 | 15 |
| Nov 5 | 29 | 47 |
| Nov 6 | 25 | 37 |
| Nov 7 | 50 | 58 |
| Nov 8 | 52 | 50 |
| Nov 9 | 55 | 59 |
| Nov 10 | 67 | 62 |
Daily averages from the CAMS atmospheric model for both places, so the week compares like with like. They can differ from today's reading at the top of the page wherever that comes from a ground station.
What it means today
Is it safe to go outside in Austin and San Antonio today?
Air quality is satisfactory for everyone. Both are in the same EPA band today (Good), so the advice is the same.
Exercise outdoors
A good day to be active outside.
Windows
Open them to air the house.
Masks
Not needed.
Air purifier
Not needed.
Against everywhere else
How do Austin and San Antonio compare with the rest of the world?
Right now Austin's air is cleaner than 82% of the 5,420 places Airleaf tracks, and San Antonio's is cleaner than 75%. Within United States, that is 77% and 62% of its 308 measured places.
Cleaner air than…
- Austin
- Beats 82%
- San Antonio
- Beats 75%
More tree cover than…
- Austin
- Beats 65%
- San Antonio
- Beats 34%
Includes model estimates as well as station readings, so it can differ from our most polluted and cleanest air rankings, which use station readings only.
Deforestation · 2001–2025
Which has lost more forest, Austin or San Antonio?
Austin has lost more: about 2,170 acres (876 ha) of forest within 10 km of its center from 2001 to 2025, against 447 acres (181 ha) around San Antonio. 2,130 acres (864 ha) of that was cleared for good, for farms, mines or towns.
Measured within 10 km of each center, from the yearly satellite maps of forest loss: a wider circle than the one for tree cover, because forest is usually lost at a city's edges.
Worst year: 2001, with 243 acres (98 ha) lost.
Worst year: 2007, with 103 acres (42 ha) lost.
| Austin | San Antonio | |
|---|---|---|
| Forest lost since 2001Cleared, burned or logged. | 2,170 acres (876 ha) | 447 acres (181 ha) (better) |
| Share of its forestOf what it had in 2000. | 12% (better) | 13% |
| Cleared for goodTurned into farms, mines or towns. | 2,130 acres (864 ha) | 415 acres (168 ha) (better) |
| Recent trend2021–2025 against the five years before. | Too little to call | Too little to call |
| Main known cause | Towns and roads (98%) | Towns and roads (81%) |
Satellite timelapses
Watch both change, year by year
A clear satellite photo a year of the land around each city. Press play, turn on the forest cleared since the first year, or drag the before and after.
Austin
2017: satellite photo from September 2017 of a 5 × 5 km area about 7 km northeast of the city center.
San Antonio
2017: satellite photo from August 2017 of a 5 × 5 km area in the city center.
Trees
Which has more trees, Austin or San Antonio?
Austin has more tree cover: 28.2% of the land within 1.2 mi (2 km) of its center against 14.7% around San Antonio, or about 86,024 trees against 46,181.
The dark mark is each place's canopy target: 30% of the land, raised where air quality is poor.
| Austin | San Antonio | |
|---|---|---|
| Trees standingEstimated from the canopy area. | 86.0K (better) | 46.2K |
| Trees still neededTo reach the target. Fewer is better. | 5.5K (better) | 48.1K |
| CO₂ absorbed each yearBy the trees already standing. | 1.9M kg (better) | 1.0M kg |
Tree cover on the satellite image
The same 1.2 mi (2 km) radius around each center, with the tree cover the satellite found marked on it.
Reading these numbers
How this comparison is made
Air quality index
The US EPA index, computed from current pollutant concentrations: ground stations where a place has them nearby, and the CAMS atmospheric model everywhere else. It moves hour to hour, so it is a snapshot rather than a verdict on either place. The guideline marks are from the WHO's 2021 air quality guidelines.
Trees and forest
Tree cover is the share of ground under canopy within 1.2 mi (2 km) of each center, read from Sentinel-2 satellite imagery at 10 m detail. It measures that circle, not the whole municipality, which is what makes the two comparable. Forest loss comes from the University of Maryland's Global Forest Change maps.
More on the method on the About Airleaf page.
Frequently asked
Austin vs San Antonio: your questions answered
Is Austin cleaner than San Antonio?
On air quality, yes, right now: Austin reads AQI 26 against 33, a gap of 7 points on the US EPA index. This is a live reading rather than an annual average, so it can reverse within a day. Over the past 7 days, on modeled daily averages, Austin averaged AQI 43 against 47, and it was the cleaner of the two on 4 of those days.
Is it safe to exercise outdoors in Austin and San Antonio today?
The advice is the same for both today. Air quality is satisfactory for everyone. Austin reads AQI 26 and San Antonio reads AQI 33.
Which has lost more forest, Austin or San Antonio?
Austin has lost more: about 2,170 acres (876 ha) of forest within 10 km of its center from 2001 to 2025, against 447 acres (181 ha) around San Antonio. 2,130 acres (864 ha) of that was cleared for good, for farms, mines or towns.
Which has more trees, Austin or San Antonio?
Austin has more tree cover: 28.2% of the land within 1.2 mi (2 km) of its center against 14.7% around San Antonio, or about 86,024 trees against 46,181. Both figures describe the same-sized circle of ground around each center, not the whole municipality.
How many more trees do Austin and San Antonio need?
Austin needs about 5,491 more to reach its canopy target of 30%, and San Antonio about 48,066 to reach 30%. The target starts at 30% of the land and rises where air quality is poor.
Are Austin and San Antonio measured the same way?
The method is the same: the US EPA index for air, and Sentinel-2 satellite imagery at 10 m detail over an identical radius for trees. Both readings come from nearby ground stations. Nothing is adjusted for population, city limits or climate.
How often does the Austin vs San Antonio comparison update?
The air readings refresh about once an hour, and each reading's local time is shown at the top of the page. Tree cover comes from the latest clear satellite image of each area (Sep 15, 2026 and Oct 20, 2026), and the forest figures are published yearly.
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