Never forget your AC filter again

Tell us when you last changed it and how often you want to be reminded — we’ll do the rest.

Enter the date you last changed or cleaned your AC filter and pick how often you want to be reminded — this tool calculates your next due date, tracks days remaining, and lets you add the reminder straight to your calendar.

When did you last change or clean the filter?

Filter size (optional)

How often do you want to change it?

— days left

Set a date to start

—

Next filter change, based on your interval

Add to Google Calendar

How the reminder works

Your next change date is your last-changed date plus your chosen interval (1, 3, or 6 months). Filters in typical single-family homes are commonly changed every 1–3 months; homes with pets, allergies, or heavy AC use often do better on the shorter end.

Which filter type do you have?

Fiberglass

The cheapest, thinnest option. Mainly protects the AC unit itself, not air quality. Change every 1–2 months.

Pleated

Denser folded material that catches more dust and allergens. Good middle ground. Change every 2–3 months.

HEPA

Traps the finest particles, best for allergies. Restricts airflow more, so check your system supports it. Change every 3–6 months.

Common questions

The size is usually printed on the edge of your current filter (e.g. 16x25x1). If it’s worn off, measure the length, width, and thickness of the frame in inches.

Not on its own — download the calendar file or add the event to Google Calendar to get a reminder on your own devices.

No, this tool doesn’t save anything between visits. Add the reminder to your calendar before you leave if you want to keep it.

It resets the countdown using today’s date and your chosen interval, so the due date moves forward automatically.

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