Size page
25x25x1 air filter: actual size, MERV, and price
Printed size 25x25x1 — actual about 24.81 × 24.81 × 0.81 (varies by brand). Pick a pack below.
MERV 13-only pack page: 25x25x1 MERV 13 (Nordic Pure MERV 13 2-, 3-, 4- and 6-pack, fit and fan notes).
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Match & price
- Nordic Pure 25x25x1 pleated (official via Awin)MERV 8 · Pack of 2$33.99$17.00 per filterPrice checked 16 OctBuy at Nordic Pure
- Nordic Pure 25x25x1 pleated (official via Awin)MERV 8 · Pack of 6$59.99$10.00 per filterPrice checked 16 OctBuy at Nordic Pure
- Nordic Pure 25x25x1 pleated (official via Awin)MERV 13 · Pack of 2$40.99$20.50 per filterPrice checked 16 OctBuy at Nordic Pure
- Nordic Pure 25x25x1 pleated (official via Awin)MERV 13 · Pack of 6$89.99$15.00 per filterPrice checked 16 OctBuy at Nordic Pure
Full answer
A 25x25x1 is a one-inch-class square furnace or AC filter. Buy the printed size 25x25x1. The panel is smaller than 25 inches on each face — Filtrete closer to 24.81 × 24.81 × 0.81 or 24.69 × 24.69 × 0.81, and Nordic Pure about 24.5 × 24.5 × 0.75. Do not substitute 24x24x1 or 20x25x1 — those are different printed sizes.
Actual dimensions by brand
Actual size by brand
These numbers are copied from manufacturer or merchant product copy, not from a competitor size chart. Thickness is part of the fit: 1-inch racks take ~¾ inch media.
| Brand | Nominal | Published actual (in.) | Source |
|---|---|---|---|
| Filtrete 25x25x1 MPR 1000 / MERV 11 | 25x25x1 | 24.81 × 24.81 × 0.81 | Amazon B07FNQT9ZY title “Actual Size 24.81 × 24.81 × 0.81 in”; product-dimensions field “24.81 × 0.81 × 24.81” |
| Filtrete 25x25x1 MPR 1000 / MERV 11 (some listings) | 25x25x1 | Title: 24.688 × 24.688 × 0.813; 4-pack dimensions field 24.69 × 24.69 × 0.81 | Amazon B09YY5Y4M1 title “Actual Size 4-Pack 24.688×24.688×0.813 in”; product-dimensions field lists 24.69 × 24.69 × 0.81 — two figures on the same family; measure if the slot is tight |
| Filtrete 25x25x1 MPR 700 / MERV 8 | 25x25x1 | 24.81 × 24.81 × 0.81 | Amazon B0DLPZ8GHR title “Actual Size 24.81 × 24.81 × 0.81 in”; product-dimensions field lists 24.81 × 24.81 × 0.81. Same actual on B0DKYZ6D8D 6-pack title |
| Filtrete 25x25x1 MPR 1500 / MERV 12 | 25x25x1 | 24.81 × 24.81 × 0.78 | Amazon B07FP5X128 title “Actual Size 24.81 × 24.81 × 0.78 in”; product-dimensions field “24.81 × 0.78 × 24.81” |
| Nordic Pure 25x25x1 pleated | 25x25x1 | Approximately 24.5 × 24.5 × 0.75 (24½ × 24½ × ¾) | JB Tools listings for Nordic Pure 25x25x1M8-6, 25x25x1M8-2, 25x25x1M13-6, and 25x25x1M13-2 |
We did not find a Honeywell Store 25x25x1 1-inch SKU (MERV 8/11/13 4-pack or 12-pack) that publishes actual dimensions, so that brand is omitted rather than guessed. We did not find an Amazon Basics 25x25x1 listing that publishes an actual-size field, so that brand is omitted rather than guessed. We did not find a Filtrete 25x25x1 MPR 1900 / MERV 13 listing that prints an actual-size field, so that grade is omitted rather than guessed. If you currently run Nordic Pure (~24.5 square) and switch to Filtrete (~24.81 or 24.69 square), expect a snugger slide-in. Filtrete’s published actuals also disagree with each other by SKU. Measure the old filter if the slot is tight. Full method: how to measure.
MERV 8 vs 11 vs 13 (EPA facts)
MERV 8 vs 11 vs 13 (facts only)
MERV is ASHRAE 52.2, as summarized by EPA. Higher MERV captures a larger share of smaller particles. It also adds resistance. EPA says to pick at least MERV 13 or as high a rating as your system fan and filter slot can accommodate, and to ask an HVAC technician if you are unsure. A 1-inch MERV 13 is not HEPA. We do not claim health outcomes.
| MERV | EPA average capture efficiency (particle size) | Typical 25x25x1 use |
|---|---|---|
| 8 | ≥20% of 1.0–3.0 µm; ≥70% of 3.0–10.0 µm | Common pleated replacement when the manual does not call for higher |
| 11 | ≥20% of 0.30–1.0 µm; ≥65% of 1.0–3.0 µm; ≥85% of 3.0–10.0 µm | Mid-grade 1-inch pleat (Filtrete MPR 1000 is commonly labeled MERV 11) |
| 13 | ≥50% of 0.30–1.0 µm; ≥85% of 1.0–3.0 µm; ≥90% of 3.0–10.0 µm | Higher-efficiency 1-inch; confirm the furnace/air handler can take the extra pressure drop |
Source: U.S. EPA, “What is a MERV rating?”, last updated 14 Jan 2026. Filtrete also prints an MPR number; MPR is 3M’s scale, not MERV. Compare MERV to MERV.
Where these prices came from
Pack prices checked 30 Aug 2026
The Nordic Pure card prices above are one-time purchase prices re-read on nordicpure.com on 16 Oct 2026 (unchanged from 6 Oct). The range and other-store notes below are public shelf/cart prices we recorded on 30 Aug 2026. They are not live. Shipping, subscribe-and-save, and store-only deals will move them. Per-filter math is pack price ÷ count, rounded to the cent.
Observed range on 30 Aug 2026 for ordinary pleated 25x25x1: about $9.00/filter at MERV 8 in a Nordic Pure 6-pack, $13.50 at MERV 13 in a Nordic Pure 6-pack, with 2-packs costing more per filter ($15.30 MERV 8; $18.45 MERV 13). Honeywell Store product URLs for 25x25x1 MERV 8/11/13 4-packs and 12-packs returned 404, so those rows are omitted rather than guessed. Walmart Filtrete product pages were not used for this check. Amazon Filtrete pages were used for actual-size fields, not for this price table. Amazon Basics had no published 25x25x1 actual-size listing. Factory one-time purchase prices for the listed MERV 8 and MERV 13 2/6-packs were re-checked 12 Oct 2026 on nordicpure.com (every card matched; MERV and pack selected) (pick MERV and pack on the factory page). A 25x25x1 is not a 24x24x1 or a 20x25x1.
Where to buy (all stores)
Where to buy
- Honeywell Store No 1-inch 25x25x1 SKU in the catalog we checked on 30 Aug 2026 (nearby listed sizes include 20x25x1): honeywellconsumerstore.com.
- Amazon Search this size: 25x25x1 furnace filter.
- AirFilters.com Custom and stock 25x25x1 cuts: airfilters.com.
- Nordic Pure Factory page (via Awin); published actual 24.5 × 24.5 × 0.75: Nordic Pure 25x25x1M8-6.
No ranking. Stock and price change. If the slot is an odd fraction that none of these actual sizes match, measure first — that is not a 25x25x1 SKU. A 24x24x1 or 20x25x1 is not a substitute.
Sources
Sources (accessed 30 Aug 2026)
- EPA MERV table: epa.gov/indoor-air-quality-iaq/what-merv-rating (updated 14 Jan 2026)
- Honeywell Store 25x25x1 MERV 8/11/13 4-pack and 12-pack product URLs returned 404; no published actual for this size
- Amazon Filtrete B07FNQT9ZY, B09YY5Y4M1, B0DLPZ8GHR, B0DKYZ6D8D, and B07FP5X128 titles (actual-size fields). No Filtrete MPR 1900 25x25x1 actual-size listing found. No Amazon Basics 25x25x1 actual-size listing found
- JB Tools Nordic Pure 25x25x1M8-2 ($30.59), 25x25x1M8-6 ($53.99), 25x25x1M13-2 ($36.89), and 25x25x1M13-6 (24.5×24.5×0.75, $80.99)