Air quality comparison · Tanzania, 122 km apart
Tanga vs Zanzibar Air quality index (AQI) today
Zanzibar has cleaner air than Tanga right now: AQI 43 (Good) against 47 (Good).
Both sit in the same EPA band, so the health advice is the same for each today. But over the past 6 days, on modeled daily averages, Tanga averaged AQI 48 against 49, and it was the cleaner of the two on 3 of those days. Zanzibar has lost more forest since 2001. Tanga has more tree cover.
Updated . Lower is better on the US EPA index: 0–50 is Good, above 300 is Hazardous. Measured by Airleaf.
Tanga47Zanzibar43
Head to head
Tanga vs Zanzibar at a glance
Tanga is ahead on 4 of 6 measures, and Zanzibar on 2. The better figure in each row is marked.
| Tanga | Zanzibar | |
|---|---|---|
| Air quality nowUS AQI. Lower is better. | 47 | 43 (better) |
| PM2.5Fine particles, µg/m³. | 7.8 | 7.3 (better) |
| Past week's averageUS AQI, 6 days. | 48 (better) | 49 |
| Forest lost since 2001Within 10 km of the center. | 1,070 ha (better) | 1,700 ha |
| Tree coverWithin 2 km of the center. | 25.8% (better) | 19.8% |
| Trees still neededTo reach a healthy canopy. | 9.5K (better) | 19.7K |
Air quality today
What is the air like in Tanga and Zanzibar right now?
Zanzibar has cleaner air than Tanga right now: AQI 43 (Good) against 47 (Good). PM2.5 is setting the index in both.
Both readings are model estimates, with no ground station close enough to either.
TangaZanzibar
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).
Tanga: Model estimate · no ground station nearby. Data: Open-Meteo / CAMS, US EPA index.
Zanzibar: Model estimate · no ground station nearby. Data: Open-Meteo / CAMS, US EPA index.
The past week
Which had cleaner air over the past 6 days?
But over the past 6 days, on modeled daily averages, Tanga averaged AQI 48 against 49, and it was the cleaner of the two on 3 of those days. Their daily figures tracked each other closely all week, so their lines nearly overlap.
- Cleaner days
- Tanga3Zanzibar1
- Average AQI
- Tanga48Zanzibar49
- Worst day, AQI
- Tanga52Zanzibar53
The daily numbers (6 days)
| Day | Tanga | Zanzibar |
|---|---|---|
| Nov 5 | 39 | 39 |
| Nov 6 | 48 | 51 |
| Nov 7 | 47 | 50 |
| Nov 8 | 52 | 53 |
| Nov 9 | 52 | 52 |
| Nov 10 | 52 | 49 |
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 Tanga and Zanzibar 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 Tanga and Zanzibar compare with the rest of the world?
Right now Tanga's air is cleaner than 64% of the 5,420 places Airleaf tracks, and Zanzibar's is cleaner than 67%. Within Tanzania, that is 58% and 67% of its 34 measured places.
Cleaner air than…
- Tanga
- Beats 64%
- Zanzibar
- Beats 67%
More tree cover than…
- Tanga
- Beats 59%
- Zanzibar
- Beats 46%
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, Tanga or Zanzibar?
Zanzibar has lost more: about 1,700 ha of forest within 10 km of its center from 2001 to 2025, against 1,070 ha around Tanga. 1,700 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: 2017, with 128 ha lost.
Worst year: 2011, with 229 ha lost.
| Tanga | Zanzibar | |
|---|---|---|
| Forest lost since 2001Cleared, burned or logged. | 1,070 ha (better) | 1,700 ha |
| Share of its forestOf what it had in 2000. | 20% (better) | 23% |
| Cleared for goodTurned into farms, mines or towns. | 1,060 ha (better) | 1,700 ha |
| Recent trend2021–2025 against the five years before. | Slowing down | Holding steady |
| Main known cause | Farms, pasture and plantations (74%) | Towns and roads (91%) |
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.
Tanga
2018: satellite photo from September 2018 of a 5 × 5 km area about 7 km north of the city center.
Zanzibar
2017: satellite photo from July 2017 of a 5 × 5 km area about 7 km east of the city center.
Trees
Which has more trees, Tanga or Zanzibar?
Tanga has more tree cover: 25.8% of the land within 2 km of its center against 19.8% around Zanzibar, or about 58,277 trees against 38,317.
The dark mark is each place's canopy target: 30% of the land, raised where air quality is poor.
| Tanga | Zanzibar | |
|---|---|---|
| Trees standingEstimated from the canopy area. | 58.3K (better) | 38.3K |
| Trees still neededTo reach the target. Fewer is better. | 9.5K (better) | 19.7K |
| CO₂ absorbed each yearBy the trees already standing. | 1.3M kg (better) | 843K 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
Tanga vs Zanzibar: your questions answered
Is Zanzibar cleaner than Tanga?
On air quality, yes, right now: Zanzibar reads AQI 43 against 47, a gap of 4 points on the US EPA index. This is a live reading rather than an annual average, so it can reverse within a day. But over the past 6 days, on modeled daily averages, Tanga averaged AQI 48 against 49, and it was the cleaner of the two on 3 of those days.
Is it safe to exercise outdoors in Tanga and Zanzibar today?
The advice is the same for both today. Air quality is satisfactory for everyone. Tanga reads AQI 47 and Zanzibar reads AQI 43.
Which has lost more forest, Tanga or Zanzibar?
Zanzibar has lost more: about 1,700 ha of forest within 10 km of its center from 2001 to 2025, against 1,070 ha around Tanga. 1,700 ha of that was cleared for good, for farms, mines or towns.
Which has more trees, Tanga or Zanzibar?
Tanga has more tree cover: 25.8% of the land within 2 km of its center against 19.8% around Zanzibar, or about 58,277 trees against 38,317. Both figures describe the same-sized circle of ground around each center, not the whole municipality.
How many more trees do Tanga and Zanzibar need?
Tanga needs about 9,487 more to reach its canopy target of 30%, and Zanzibar about 19,739 to reach 30%. The target starts at 30% of the land and rises where air quality is poor.
Are Tanga and Zanzibar 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 are model estimates, with no ground station close enough to either. Nothing is adjusted for population, city limits or climate.
How often does the Tanga vs Zanzibar 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 6, 2026 and Sep 16, 2026), and the forest figures are published yearly.
Keep going
Compare them with somewhere else
Build your own
Compare Tanga with somewhere else
This place
Tanga