Air quality comparison · South Africa, 1262 km apart
Cape Town vs Johannesburg Air quality index (AQI) today
Cape Town has cleaner air than Johannesburg right now: AQI 63 (Moderate) against 83 (Moderate).
Both sit in the same EPA band, so the health advice is the same for each today. Over the past 6 days, on modeled daily averages, Cape Town averaged AQI 69 against 70, and it was the cleaner of the two on 5 of those days. Cape Town has lost more forest since 2001. Cape Town has more tree cover.
South Africa
AQI 63
Moderate
Cleaner right now
- PM2.5
- 15.8 µg/m³1.1× WHO guideline
- Main pollutant
- PM2.5
- Source
- Ground station
- Reading
- Nov 11, 21:00 local
South Africa
AQI 83
Moderate
Cleaner right now
- PM2.5
- 26.4 µg/m³1.8× WHO guideline
- Main pollutant
- PM2.5
- Source
- Ground station
- Reading
- Nov 11, 21:00 local
Updated . Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous. Measured by Airleaf.
Cape Town63Johannesburg83
Head to head
Cape Town vs Johannesburg at a glance
Cape Town is ahead on 5 of 6 measures, and Johannesburg on 1. The better figure in each row is marked.
| Cape Town | Johannesburg | |
|---|---|---|
| Air quality nowUS AQI. Lower is better. | 63 (better) | 83 |
| PM2.5Fine particles, µg/m³. | 15.8 (better) | 26.4 |
| Past week's averageUS AQI, 6 days. | 69 (better) | 70 |
| Forest lost since 2001Within 10 km of the center. | 642 ha | 9 ha (better) |
| Tree coverWithin 2 km of the center. | 15.2% (better) | 4.2% |
| Trees still neededTo reach a healthy canopy. | 43.1K (better) | 81.1K |
Air quality today
What is the air like in Cape Town and Johannesburg right now?
Cape Town has cleaner air than Johannesburg right now: AQI 63 (Moderate) against 83 (Moderate). PM2.5 is setting the index in both.
Cape Town's PM2.5 is about 1.1× the WHO's 24-hour guideline of 15 µg/m³. Johannesburg's PM2.5 is about 1.8× the WHO's 24-hour guideline of 15 µg/m³.
Both readings come from nearby ground stations.
Cape TownJohannesburg
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).
Cape Town: Ground station · Foreshore-NAQI, 1.3 km away · median of 4 stations. Data: OpenAQ · South Africa, South African Air Quality Information System (SAAQIS).
Johannesburg: Ground station · Little John Park , 10.6 km away · median of 3 stations. Data: OpenAQ · AirGradient, South Africa, Shift iT, Robin Kohl, South African Air Quality Information System (SAAQIS).
The past week
Which had cleaner air over the past 6 days?
Over the past 6 days, on modeled daily averages, Cape Town averaged AQI 69 against 70, and it was the cleaner of the two on 5 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
- Cape Town5Johannesburg1
- Average AQI
- Cape Town69Johannesburg70
- Worst day, AQI
- Cape Town97Johannesburg92
The daily numbers (6 days)
| Day | Cape Town | Johannesburg |
|---|---|---|
| Nov 5 | 75 | 92 |
| Nov 6 | 57 | 68 |
| Nov 7 | 55 | 72 |
| Nov 8 | 56 | 57 |
| Nov 9 | 97 | 54 |
| Nov 10 | 75 | 78 |
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 Cape Town and Johannesburg today?
Unusually sensitive people should consider limiting long outdoor exertion. Both are in the same EPA band today (Moderate), so the advice is the same.
Exercise outdoors
Fine for most people; unusually sensitive people should take long or hard exercise easier.
Windows
Fine to open; close them if you are sensitive to pollution.
Masks
Not needed for most people.
Air purifier
Worth running if you are sensitive.
Against everywhere else
How do Cape Town and Johannesburg compare with the rest of the world?
Right now Cape Town's air is cleaner than 45% of the 5,420 places Airleaf tracks, and Johannesburg's is cleaner than 29%. Within South Africa, that is 60% and 35% of its 66 measured places.
Cleaner air than…
- Cape Town
- Beats 45%
- Johannesburg
- Beats 29%
More tree cover than…
- Cape Town
- Beats 35%
- Johannesburg
- Beats 8%
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, Cape Town or Johannesburg?
Cape Town has lost more: about 642 ha of forest within 10 km of its center from 2001 to 2025, against 9 ha around Johannesburg. 139 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: 2018, with 147 ha lost.
Worst year: 2019, with 2 ha lost.
| Cape Town | Johannesburg | |
|---|---|---|
| Forest lost since 2001Cleared, burned or logged. | 642 ha | 9 ha (better) |
| Cleared for goodTurned into farms, mines or towns. | 139 ha | 7 ha (better) |
| Recent trend2021–2025 against the five years before. | Too little to call | Too little to call |
| Main known cause | Wildfires (63%) | Towns and roads (76%) |
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.
Cape Town
2017: satellite photo from March 2017 of a 5 × 5 km area about 7 km southwest of the city center.
Johannesburg
2017: satellite photo from August 2017 of a 5 × 5 km area in the city center.
Trees
Which has more trees, Cape Town or Johannesburg?
Cape Town has more tree cover: 15.2% of the land within 2 km of its center against 4.2% around Johannesburg, or about 44,219 trees against 13,195.
The dark mark is each place's canopy target: 30% of the land, raised where air quality is poor.
| Cape Town | Johannesburg | |
|---|---|---|
| Trees standingEstimated from the canopy area. | 44.2K (better) | 13.2K |
| Trees still neededTo reach the target. Fewer is better. | 43.1K (better) | 81.1K |
| CO₂ absorbed each yearBy the trees already standing. | 973K kg (better) | 290K kg |
Tree cover on the satellite image
The same 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 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
Cape Town vs Johannesburg: your questions answered
Is Cape Town cleaner than Johannesburg?
On air quality, yes, right now: Cape Town reads AQI 63 against 83, a gap of 20 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 6 days, on modeled daily averages, Cape Town averaged AQI 69 against 70, and it was the cleaner of the two on 5 of those days.
Is it safe to exercise outdoors in Cape Town and Johannesburg today?
The advice is the same for both today. Unusually sensitive people should consider limiting long outdoor exertion. Cape Town reads AQI 63 and Johannesburg reads AQI 83.
Which has lost more forest, Cape Town or Johannesburg?
Cape Town has lost more: about 642 ha of forest within 10 km of its center from 2001 to 2025, against 9 ha around Johannesburg. 139 ha of that was cleared for good, for farms, mines or towns.
Which has more trees, Cape Town or Johannesburg?
Cape Town has more tree cover: 15.2% of the land within 2 km of its center against 4.2% around Johannesburg, or about 44,219 trees against 13,195. Both figures describe the same-sized circle of ground around each center, not the whole municipality.
How many more trees do Cape Town and Johannesburg need?
Cape Town needs about 43,055 more to reach its canopy target of 30%, and Johannesburg about 81,053 to reach 30%. The target starts at 30% of the land and rises where air quality is poor.
Are Cape Town and Johannesburg 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 Cape Town vs Johannesburg 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 (Mar 15, 2026 and Sep 14, 2026), and the forest figures are published yearly.
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