The replacement cycle of an air filter is not an absolutely fixed figure; it is influenced by various factors. However, we can provide a general reference range and some specific situations that need to be considered:

General reference period
Under normal circumstances, most car manufacturers recommend a replacement cycle of every 10,000 to 20,000 kilometers, or every 6 months to 1 year (whichever comes first). This range applies to most urban roads and regular driving conditions.
For specific vehicle models: The most accurate source of information is your vehicle user manual. The manual usually provides specific replacement suggestions based on driving mileage and/or time. The recommended cycle may vary slightly among different brands and models of vehicles.

Key factors affecting the replacement cycle
Driving environment: This is the most important factor affecting the replacement cycle.
Harsh environments: If you frequently drive on dusty, sandy roads, near construction sites, in agricultural areas or in coastal salt spray conditions, the impurities in the air will far exceed those on urban roads. In this case, the air filter will clog up more quickly. You need to shorten the replacement cycle, and it may need to be checked or replaced every 5,000 kilometers or even less.
Good environment: If the vehicle is mainly driven in cities with good air quality and clean roads or on highways, the service life of the filter will be relatively long, approaching or reaching the upper limit recommended by the manufacturer.
Driving habits
Frequent short-distance starts: If the engine is frequently driven for short distances, it may stall before reaching its normal operating temperature. This is not conducive to the removal of carbon deposits and may also put more burden on the filter.
Intense driving: Frequent sharp acceleration and high-speed driving may cause the engine to draw in more air (theoretically), but the main impact is still environmental factors.