In 2025, Beijing delivered impressive air quality results, with its annual average PM2.5 concentration falling to 27.0 μg/m3. For the first time, the city met the “below 30” benchmark, while the share of days with good air quality exceeded 80% and days with heavy pollution were largely eliminated. How significant is this achievement for Beijing? And how did air quality perform across the rest of China over the past year? Blue Map takes you through an hour-by-hour review.