Air Purifier Ownership Cost Calculator

Use the power of the actual mode

Use the watts of the fan setting you actually run and the daily hours. Continuous use adds up even at modest power.

An automatic mode may change fan power as air conditions change. A plug meter can give representative kWh; average watts are measured kWh × 1,000 divided by measured hours. Alternatively, model the setting used most often. Check whether a label wattage is operating input or only its maximum rating.

Count filter replacements

Enter the price per complete replacement set and the annual number from your model manual or replacement history. Do not count washable filters as new purchases.

A filter set should reflect what is actually replaced at each interval. Some models have multiple filter layers with different schedules. If schedules differ, first estimate the real annual filter spend and choose equivalent set price and count. Availability of genuine replacements and delivery charges can matter as much as the device price.

Worked default example

45 W × 12 hours × 365 days = 197.1 kWh/year. At THB 4.5/kWh, electricity is THB 886.95. Two filters at THB 1,200 cost THB 2,400, for THB 3,286.95 recurring per year; the blank purchase price is excluded.

With an entered THB 6,000 purchase price and the default three years, the estimate becomes 6,000 + 3 × 3,286.95 = THB 15,860.85. Compare two models over the same years and operating hours, so a low purchase price with expensive filters does not appear cheaper by accident.

Compare over the same period

With a device price entered, total cost adds recurring costs over the selected years. It assumes constant prices and use, and excludes repairs or replacement of the device.

Annual filter count is an assumption, not a universal replacement schedule. Dust, smoke and manufacturer instructions can change intervals. Ownership cost also says nothing about clean-air delivery, noise or appropriate room size, so check those separately before choosing a model.

When comparing models, use the same electricity rate and years for both. Check that filter-set prices include comparable parts, whether starter filters come with the device, and whether replacements are locally available. Cost is useful only alongside filtration performance and noise suitable for the actual room.