// tool 05 · your city in cigarettes

Air quality cigarette equivalent, by city

Type the city you live in and watch its air turn into cigarettes. The number comes from the city's official annual PM2.5 measurement in the WHO air quality database and the Berkeley Earth rule of thumb that 22 µg/m³ of PM2.5 ≈ one cigarette a day.

Try:

Pick a city and the cigarettes light up. The number is what a year-round resident breathes in on an average day, based on the city's latest annual-mean PM2.5 in the WHO database.

Why compare air quality to cigarettes?

Nobody has a feel for "12 micrograms per cubic metre". Everybody has a feel for a cigarette. Both city air and tobacco smoke deliver the same damaging ingredient, fine particulate matter (PM2.5), so you can line up the particle dose from a year of breathing your city against the particle dose from a cigarette and get a number that means something.

Two things to keep in mind. First, this is an annual average: a bad winter week in Delhi or a wildfire day in Seattle is far worse than the year-round figure. Second, it is a dose analogy for particles only. Cigarette smoke also carries nicotine, tar and hundreds of other chemicals that outdoor air does not, so "half a cigarette a day" is a way to feel the scale, not a claim that the two are chemically the same.

How it works

For every city, WHO publishes an annual-mean PM2.5 concentration measured by that city's official monitoring stations (urban background stations, chosen to represent what residents breathe rather than a single roadside spot). We take the most recent year available and divide by the per-cigarette figure:

cigarettes/day = annual-mean PM2.5 (µg/m³) ÷ 22
Berkeley Earth PM2.5 dose equivalence, applied to the WHO annual mean

The yearly total is simply that figure times 365, and a pack is 20 cigarettes. The category badge and the US AQI shown for context use the EPA's 2024 PM2.5 breakpoints, and the "× WHO guideline" line compares the city to the WHO 2021 annual guideline of 5 µg/m³.

Big cities, in cigarettes a day

Latest WHO annual mean for each city. Click a row to load it in the tool.

CityPM2.5 µg/m³YearCig / dayCig / year
Delhi, India107.020214.91,775
Lahore, Pakistan96.02023*4.41,593
Dhaka, Bangladesh90.52023*4.11,501
Istanbul, Turkey50.520252.3837
Mumbai, India49.520212.3821
Kolkata, India48.020212.2796
Karachi, Pakistan44.320192.0735
Sao Paulo, Brazil37.220241.7617
Kathmandu, Nepal37.020201.7614
Beijing, China31.020241.4514
Shanghai, China28.420241.3472
Jakarta, Indonesia28.32025*1.3470
Bangkok, Thailand23.420211.1389
Santiago, Chile21.82024*0.99362
Milano, Italy20.420240.93339
Mexico City, Mexico20.02023*0.91332
Kuala Lumpur, Malaysia19.12024*0.87317
Seoul, South Korea17.62024*0.80292
Hong Kong, China14.62025*0.66242
Singapore, Singapore12.02025*0.55199
Berlin, Germany11.320240.51188
Los Angeles, United States10.520220.48175
Madrid, Spain10.320240.47170
London, United Kingdom10.02025*0.45166
Tokyo, Japan9.52025*0.43158
Toronto, Canada9.420230.43156
Paris, France9.320240.42154
New York, United States7.120220.32117
Sydney, Australia6.22025*0.28103
Seattle, United States6.120220.28101
Stockholm, Sweden4.920240.2281

Source: WHO Ambient Air Quality Database V8.0 (June 2026), latest year per city. * = newer figure from the city's or country's own environment agency (listed under Sources below). Names are shortened for readability; the WHO label sometimes covers a whole metro area.

Frequently asked questions

Type your city into the tool above. It looks up the city's latest annual-mean PM2.5 in the WHO Ambient Air Quality Database and divides by 22 µg/m³, the Berkeley Earth figure for the fine-particle dose of one cigarette. Delhi comes out at roughly five cigarettes a day; New York, Seattle and Stockholm sit well under half a cigarette a day.

An average. The WHO database publishes one annual-mean PM2.5 value per city per year, from that city's official monitoring stations. So the cigarette number is what a resident breathes on a typical day over a whole year, not a live reading. On a wildfire or smog day the real figure can be ten times higher, which is exactly why a personal monitor is useful.

From the WHO Ambient Air Quality Database, version 8.0 (June 2026). WHO compiles it from official national and sub-national monitoring networks (the European Environment Agency for EU countries), covering 8,000+ settlements in 127 countries with measurements from 2010 to 2024. We use each city's most recent year and show that year next to the result. For a dozen major cities whose WHO row is several years old or missing (London, Tokyo, Seoul, Hong Kong, Singapore, Kuala Lumpur, Jakarta, Lahore, Dhaka, Santiago, Sydney, Mexico City) we use the newer annual mean published by the city's or country's own environment agency, linked next to the number.

It is the equivalence published by Berkeley Earth physicists Richard and Elizabeth Muller in 2015. They compared the death rate from smoking (about 1.37 deaths per million cigarettes) with the mortality attributed to PM2.5 exposure, and found that living at 22 µg/m³ of PM2.5 carries roughly the same risk as one cigarette per day. It is a rule of thumb, not a medical equivalence, and it only covers fine particles, not nicotine or the other chemicals in tobacco smoke.

The WHO database only includes places with official ground monitoring that report to WHO, so smaller towns and some countries are missing. Use the 'Near me' button to find the closest monitored city, or if you know a PM2.5 or AQI reading for your area, the AQI to cigarettes calculator converts it directly.

No. The US AQI is a 0–500 scale built from pollutant concentrations, and it is not linear in PM2.5. We show the AQI that corresponds to each city's annual-mean PM2.5 for context, but the cigarette equivalence is calculated from the PM2.5 concentration itself, which is what the WHO publishes.

Sources

City figures newer than the WHO database

For these cities WHO's latest row is several years old or missing, so the tool uses the annual mean published by the city's or country's own environment agency. Where the agency publishes only per-station values, the figure is our plain average of those stations and says so.

That's the city average. What about your air?

The number above is one station's yearly mean. Your commute, your kitchen and your bedroom are all different. Partycle is a small clip-on PM2.5 and CO₂ sensor that shows the cigarettes you actually breathe, day by day. I'm building it in the open, and I'll email you when it ships.