---
title: "16x21x1 Air Filters — $361K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/tools-home-improvement/16x21x1-air-filters"
last_updated: "2026-08-08T08:53:27.777Z"
locale: en
meta:
description: "Niche score 58/100 · $361K/yr market. A failed launch gate (market size, growth, or returns) keeps it on the watch list. Data updated Jul 2026."
"og:description": "Niche score 58/100 · $361K/yr market. A failed launch gate (market size, growth, or returns) keeps it on the watch list. Data updated Jul 2026."
"og:title": "16x21x1 Air Filters — $361K/yr Amazon US Niche (2026) - Flapen"
---
# **16x21x1 air filters**
**Worth a look**
Shows a sweet-spot price point ($44.79 avg), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.
Market size 54Growth 64Conversion 88Competition 45Returns 90Price range 95Avg price 95Brand share 28Review moat 24Quality gap 20
**Avg price**
**Incredible****$44.79**
avg listing price — sweet spot $15–$100
**Price range**
**Incredible****$25.59–$63.36**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Returns**
**Great****1.3%**
return rate — above 5% kills the launch gate
**Conversion**
**Great****10.3%**
search→purchase rate — share of searches ending in a sale
**Growth**
**Good****+41.8%**
90-day search growth — must beat 0% to launch
**Market size**
**Good****$361K**
$361K/yr · 78K searches
**Competition**
**Okay****58%**
top-5 click share — leaders hold, buyers still browse
**Brand share**
**Okay****88%**
top-5 brand share — brands hold most of the demand
**Review moat**
**Bad****6,282.52**
avg incumbent reviews — the moat a new listing must climb
**Quality gap**
**Bad****4.7★**
avg incumbent rating — lower means beatable quality
According to Flapen's Amazon United States niche tracking, 16x21x1 air filters is a $361K/yr Amazon United States market (78K searches/yr). The top 5 brands hold 88% of demand. Demand peaks in Jul. Verdict: Worth a look — 58/100.
Data updated Jul 27, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **16x21x1 air filters market data**
- **Units sold / yr**
- **8K–10K**
- avg 500–750/product
- **Revenue / yr**
- **$358K–$448K**
- units × avg price
- **Conversion rate**
- **10.3%**
- **Avg BSR**
- **#171**
- **Page quality**
- **0%**
- **Prime**
- **76%**
- **Sponsored**
- **71%**
- **Out of stock**
- **5.7%**
- **Avg brand age**
- **63 months**
- **Avg seller age**
- **193 days**
## **Competition & brand share**
The top 5 products take 58% of clicks — established leaders, but buyers still shop beyond them.
**Brands**
**11 **▲rising
**Sellers**
**17**
**Top-5 brand share**
**88%**
Top 20: 100%
**Top-5 click share**
**58%**
Top 20: 99%
**Open market**
**9%**
- Aerostar53% - Filtrete13% - Chenzhit10% - Glasfloss9% - Amazon Basics4% - Qingzhug3% - Open — no brand owns it (5 brands, 9%)
## **Demand & seasonality**
Weekly Amazon search volume, last 103 weeks — +41.8% search growth over the last 90 days.
30K20KSpike '25Prime Day '25Holiday '25Spike '26Prime Day '26 seasonDecMarJunAugNovMarMay
Peak months: Jul · busiest ÷ quietest = 8.5×
[**Open Trend **](https://flapen.com/research/us/tools-home-improvement/16x21x1-air-filters/trend)
## **Top 16x21x1 air filters search terms**
- **16 3/8 x 21 1/2 x 1 air filter**28K/yr+44.7%13.2% conv. - **16x21x1 air filters**14K/yr+25.2%5.8% conv. - **16x21x1 air filter**7K/yr+75.6%1.9% conv. - **air filter 16x21x1**6K/yr+56.8%2.1% conv. - **16x21x1 furnace filter**6K/yr+14.9%0.6% conv. - **furnace filters 16x21x1**4K/yr+74.8%0.7% conv. - **air filter 16 3/8 x 21 1/2 x 1**5K/yr+25.2%14.8% conv. - **ac filter 16 3/8 x 21 1/2 x1**4K/yr+70.4%12.1% conv. - **16 x 21 x 1 air filter**3K/yr+50.9%4.5% conv. - **aerostar 16 3/8 x 21 1/2 x 1**3K/yr+3.3%13.9% conv. [**All search terms **](https://flapen.com/research/us/tools-home-improvement/16x21x1-air-filters/search-terms)
## **Top 16x21x1 air filters products on Amazon**
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
0%10%$36K20%$72K30%$108K40%$144K101001K10K100K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 21 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Aerostar 16.375x21.5x1 MERV 11 Air Filter 4 Count ACTUAL SIZE (16.50 x 21.50 x 0.75) HVAC Air Conditioning & Furnace Filter for Dust Pet Dander Smoke & Allergies (MPR 1200 / FPR 7) Made in USA**Aerostar**$33.33**4.7★4,106 rev](https://www.amazon.com/dp/B0813SW6FK) [2**Aerostar 16.375x21.5x1 MERV 8 Air Filter 6 Count ACTUAL SIZE (16.50 x 21.50 x 0.75) HVAC Air Conditioning & Furnace Filter Captures Dust Lint & Pollen (MPR 600 / FPR 5) Made in USA**Aerostar**$45.88**4.6★3,658 rev](https://www.amazon.com/dp/B073VGH6T7) [3**Chenzhit (6 Pack) 16 3/8x21 1/2x1 Furnace Air Filters MPR 1900 & FPR 10 MERV 13 Pleated Air Filter (Actual Size: 16 3/8x21 1/2x3/4)**Chenzhit**$58.61**4.7★647 rev](https://www.amazon.com/dp/B0DZSY2SDH) [4**Glasfloss 16-3/8x21-1/2x1 MERV 10 Air Filters 6-Pack Fits Carrier**Glasfloss**$60.30**4.8★2,728 rev](https://www.amazon.com/dp/B089KTMQ4D) [5**Aerostar 16.375x21.5x1 MERV 11 - 6 Count - Pleated HVAC Furnace & Air Conditioner Filters - Removes Dust Cold & Flu Germs Lint Mold Pet Dander Allergy-Causing Pollen Smog & Smoke**Aerostar**$48.21**4.7★4,106 rev](https://www.amazon.com/dp/B01CR9JCLE)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**(6 Pack) 16 3/8x21 1/2x1 Air Filter MERV 13 MPR 1900 & FPR 10 Pleated Air Filter (Actual Size: 16 3/8x21 1/2x0.75)**Fxnitang**$56.21**54 rev3mo ago](https://www.amazon.com/dp/B0GVDQN1YM) [**Filtrete 16x21x1 AC Furnace Air Filter MPR 700 MERV 8 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 2-Pack (Actual Size 15.69 x 20.69 x 0.81 in)**Filtrete**$25.59**740 rev1y ago](https://www.amazon.com/dp/B0F9LSBST9) [**Filtrete 16x21x1 Air Filter MERV 11 MPR 1000 Allergens & Pet Dander 3-Month AC and Furnace Filters Cleaner Air Reliable Airflow 4 HVAC Filters (Actual Size 15.68 x 20.68 x 0.81 in)**Filtrete**$53.98**25,454 rev1y ago](https://www.amazon.com/dp/B0F9LTBKDL) [**Chenzhit (6 Pack) 16 3/8x21 1/2x1 Furnace Air Filters MPR 1900 & FPR 10 MERV 13 Pleated Air Filter (Actual Size: 16 3/8x21 1/2x3/4)**Chenzhit**$58.61**647 rev1y ago](https://www.amazon.com/dp/B0DZSY2SDH) [**Filtrete 16x21x1 AC Furnace Air Filter MPR 700 MERV 8 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 6-Pack (Actual Size 15.69 x 20.69 x 0.81 in)**Filtrete**$42.93**627 rev1y ago](https://www.amazon.com/dp/B0DKY7H8FL)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**(6 Pack) 16 3/8x21 1/2x1 Air Filter MERV 13 MPR 1900 & FPR 10 Pleated Air Filter (Actual Size: 16 3/8x21 1/2x0.75)**Fxnitang**$56.21**4.7★**▲ 211%**](https://www.amazon.com/dp/B0GVDQN1YM) [**Aerostar 16.375x21.5x1 MERV 8 Air Filter 6 Count ACTUAL SIZE (16.50 x 21.50 x 0.75) HVAC Air Conditioning & Furnace Filter Captures Dust Lint & Pollen (MPR 600 / FPR 5) Made in USA**Aerostar**$45.88**4.6★**▲ 154%**](https://www.amazon.com/dp/B073VGH6T7) [**Glasfloss 16-3/8x21-1/2x1 MERV 10 Air Filters 6-Pack Fits Carrier**Glasfloss**$60.30**4.8★**▲ 107%**](https://www.amazon.com/dp/B089KTMQ4D) [**16 3/8 x 21 1/2 x 1 Air Filter Frame with High Air Flow Washable Reusable Media Compatible Replacement for Fan Coil Filter KFAFK0212MED 317659-402 -MERV 5 Made in USA AC HVAC Furnace Filter Holder**CoreCarbon**$63.36**4.9★**▲ 91%**](https://www.amazon.com/dp/B0CF62PDTG) [**Filtrete 16x21x1 AC Furnace Air Filter MPR 700 MERV 8 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 2-Pack (Actual Size 15.69 x 20.69 x 0.81 in)**Filtrete**$25.59**4.7★**▲ 56%**](https://www.amazon.com/dp/B0F9LSBST9)
**~~View all trending →~~**
## **What buyers say about 16x21x1 air filters**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Value For Money**26%
*“Best value”*
**Size-Overall**16%
*“Fits and reasonable”*
**Filtration**15%
*“Good filters”*
**Quality-Overall**15%
*“Good quality”*
**Advertised Vs Actual Product**5%
*“As advertised”*
**Efficiency**4%
*“Basic does the job”*
**Ease Of Use**2%
*“Easy to use”*
**Spray/Flow**2%
*“Easy to install good air flow”*
**Compatibility-Overall**1%
*“Compatibility just as good as comparable name brands and the size and fit is perfect”*
**Ease Of Cleaning**1%
*“Clean air”*
### **What buyers complain about **
**Size-Overall**21%
*“Too big”*
**Filtration**18%
*“Terrible air filter”*
**Quality-Overall**14%
*“Poor Quality Control”*
**Strength**14%
*“Very flimsy”*
**Value For Money**5%
*“Good price item did not arrive until 3 days later”*
**Durability**4%
*“Within a couple weeks theyre broken”*
**Thickness**3%
*“know that the filters that are the thickest are not the best for your furnace”*
**Functionality-Overall**2%
*“It doesnt make the job”*
**Flexibility**2%
*“Didnt like the filters easily bends”*
**Adhesion/Stickiness**2%
*“No glue around edges”*
### **Top return reasons **
**Size-Overall**77%
**Filtration**12%
**Compatibility-Overall**4%
**Advertised Vs Actual Product**1%
**Value For Money**1%
**Quality-Overall**1%
**Strength**1%
**Defective Material/Parts**1%
**Functionality-Overall**0%
**Thickness**0%
## **Common questions**
- **Is 16x21x1 air filters profitable to sell on Amazon United States?**
- The niche generates $361K/yr across 21 tracked products. 0 of 1 products launched in the last 360 days are still selling. 90-day search growth is +41.8%. Flapen's verdict: Worth a look (58/100).
- **How competitive is the 16x21x1 air filters niche?**
- 11 brands and 17 sellers compete. The top 5 products take 58% of clicks and top 5 brands hold 88% of demand.
- **What do buyers complain about in 16x21x1 air filters?**
- Top complaints mined from reviews: Size-Overall, Filtration, Quality-Overall. The return rate is 1.3%.
- **When does demand for 16x21x1 air filters peak?**
- Demand peaks in Jul; the busiest month runs 8.5× the quietest.
- **What does it cost to enter the 16x21x1 air filters niche?**
- Listings span $25.59–$63.36; the average listing price is $44.79 (sweet spot $15–$100). The average incumbent carries 6,283 reviews — the moat a new listing must climb.
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