SmogRank / Estonia / Harjumaa / Tallinn

Tallinn, month by month

Tallinn has a measured daily mean on 709 days since 27 March 2024. Its worst month was January 2026, at 47 US AQI (8.5 µg/m³), 1,620th of 2,978 cities on that month's world ranking. Its cleanest was December 2024, at 11 US AQI (2.0 µg/m³).

Every month since 2024

202625 so far271 days measured3,113th of 3,214 in the world
Jan47#1,620Feb39#2,455Mar34#2,806Apr17#3,241May21#3,071Jun21#3,056Jul13#3,029Aug18#3,185Sep13#3,322Oct19#3,049
202521 for the year280 days measured2,893rd of 2,926 in the world
Jan18#2,709Feb31#2,442Mar26#2,778Apr18#3,082May21 daysJun18 daysJul30#2,639Aug15#3,086Sep21#3,104Oct13 daysNov20#2,828Dec13#3,178
2024too few days for a mean (a year needs 257)158 days measured
JanFebMar2 daysApr20#2,313May28#2,246Jun9 daysJul14#2,553Aug11 daysSepnoneOct12 daysNov19 daysDec11#2,602
Each square is a month's mean PM2.5 in US AQI from Tallinn's measured days, with its place on that month's world ranking under it. A month has a mean once 70% of its days are measured, the rule the monthly rankings use; under that, the square gives the days measured. Each square opens that month's ranking with Tallinn marked; each year, the year's. A dashed square is the running month, so far.
Good0–50
Moderate51–100
Unhealthy for sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Months without a mean, and why

9 months
MonthWhy
Oct 202513 of 31 days measured; a month needs 22. The others: 18 with readings for part of the day (a day needs 18 hours).
Jun 202518 of 30 days measured; a month needs 21. The others: 12 with readings for part of the day (a day needs 18 hours).
May 202521 of 31 days measured; a month needs 22. The others: 1 with no readings from the monitor, 9 with readings for part of the day (a day needs 18 hours).
Nov 202419 of 30 days measured; a month needs 21. The others: 11 with under 18 hours of readings or readings that failed our checks.
Oct 202412 of 31 days measured; a month needs 22. The others: 19 with under 18 hours of readings or readings that failed our checks.
Sep 2024No day measured. The others: 30 with under 18 hours of readings or readings that failed our checks.
Aug 202411 of 31 days measured; a month needs 22. The others: 20 with under 18 hours of readings or readings that failed our checks.
Jun 20249 of 30 days measured; a month needs 21. The others: 21 with under 18 hours of readings or readings that failed our checks.
Mar 20242 of 31 days measured; a month needs 22. The others: 3 with under 18 hours of readings or readings that failed our checks.

A day counts once 18 hours of it are measured; a month needs 70% of its days.

Tallinn's worst months

MonthUS AQIDays measuredWorld rank
January 2026 478.5 µg/m³31 of 311,620thof 2,978
February 2026 397.1 µg/m³27 of 282,455thof 3,180
March 2026 346.2 µg/m³31 of 312,806thof 3,285
February 2025 315.6 µg/m³22 of 282,442ndof 2,852
July 2025 305.4 µg/m³31 of 312,639thof 3,073
May 2024 285.1 µg/m³29 of 312,246thof 2,684

Monthly means over the days measured; finished months only. World rank: its place on that month's world ranking of every city with enough days. Each month opens that ranking.

Tallinn's worst days

DayUS AQI
1 Jan 2026 8225.8 µg/m³
24 Feb 2025 7320.7 µg/m³
12 Mar 2026 6919.0 µg/m³
11 Mar 2026 6717.8 µg/m³
19 Jan 2026 6717.5 µg/m³
16 Jan 2026 6516.6 µg/m³
25 Mar 2026 6516.6 µg/m³
10 Mar 2026 6416.0 µg/m³
17 Jan 2026 6315.5 µg/m³
9 Mar 2026 6315.4 µg/m³

Daily means, the highest since 27 Mar 2024; the WHO's daily guideline is 15 µg/m³. Each date opens that day's world ranking, and each episode the bad-air spell it was part of.

Use this history

SmogRank, PM2.5 monthly and daily means, Tallinn, Estonia, 27 Mar 2024 – 10 Oct 2026. Monitor data from EEA, via OpenAQ and from the publisher directly; sources listed at smogrank.com/sources. smogrank.com/ee/tallinn/history (accessed 13 Oct 2026).

Download chart (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Tallinn now: the last 24 hours, its ranks today and the last 12 months day by day.

Updated 2026-10-13 21:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some low-cost readings: Sensor.Community, ODbL (data and licence). Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); RMCAB (Secretaría Distrital de Ambiente, Bogotá); Love My Air (City and County of Denver), no reuse terms published (why we use them).