Is 17.5x21x1 air filter profitable to sell on Amazon United States?

The niche generates $31K/yr across 8 tracked products. 0 of 2 products launched in the last 360 days are still selling. 90-day search growth is +24.4%. Flapen's verdict: Skip it (42/100).

How competitive is the 17.5x21x1 air filter niche?

6 brands and 14 sellers compete. The top 5 products take 91% of clicks and top 5 brands hold 97% of demand.

What do buyers complain about in 17.5x21x1 air filter?

Top complaints mined from reviews: Filtration. The return rate is 0.7%.

What does it cost to enter the 17.5x21x1 air filter niche?

Listings span $38.40–$75.13; the average listing price is $49.40 (sweet spot $15–$100). The average incumbent carries 2,359 reviews — the moat a new listing must climb.

17.5x21x1 air filter

Skip it

Brand-locked demand (top 5 brands take 97% of clicks) — this niche doesn't clear our bar today.

Returns

Incredible0.7%

return rate — above 5% kills the launch gate

Price range

Incredible$38.40–$75.13

cheapest to priciest tracked listing — scored on the share inside $15–$100

Avg price

Great$49.40

avg listing price — sweet spot $15–$100

Conversion

Great7.5%

search→purchase rate — share of searches ending in a sale

Growth

Good+24.4%

90-day search growth — must beat 0% to launch

Review moat

Okay2,358.88

avg incumbent reviews — the moat a new listing must climb

Quality gap

Bad4.7★

avg incumbent rating — lower means beatable quality

Market size

Bad$31K

$31K/yr · 8K searches

Competition

Bad91%

top-5 click share — a locked-up shelf

Brand share

Bad97%

top-5 brand share — brand-locked demand

According to Flapen's Amazon United States niche tracking, 17.5x21x1 air filter is a $31K/yr Amazon United States market (8K searches/yr). The top 5 brands hold 97% of demand. Verdict: Skip it — 42/100.

Data updated Jul 27, 2026 · scored weekly · How we score niches

17.5x21x1 air filter market data

Units sold / yr: 750–1K; avg 100–250/product
Revenue / yr: $37K–$49K; units × avg price
Conversion rate: 7.5%
Avg BSR: #581
Page quality: 0%
Prime: 38%
Sponsored: 38%
Out of stock: 3.4%
Avg brand age: 73 months
Avg seller age: 229 days

Competition & brand share

The top 5 products capture 91% of clicks — a locked-up shelf that new listings rarely crack.

Brands

6 flat

Sellers

Top-5 brand share

97%

Top 20: 100%

Top-5 click share

91%

Top 20: 100%

Open market

Filter King51%
SpiroPure22%
Filtrete10%
WholesaleHVACDirect10%
QCYZTL4%
Glasfloss3%
Open — no brand owns it (0%)

Top 17.5x21x1 air filter 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.

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)1 product missing review or click data not plotted

All 8 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Filter King 17.5x21x1 Air Filter (MERV 8) (4-Pack) Dust & Allergy Control AC Furnace Filters MADE IN USA HVAC Pleated Electrostatic (Actual Size: 17.5 x 21 x .75)

Filter King$51.254.7★4,436 rev

SpiroPure 17.5X21X1 MERV 8 Geothermal Air Filters - Made in USA (6 Pack)

SpiroPure$52.774.7★325 rev

WholesaleHVACDirect 17.5x21x1 Air Filter (MERV 8) (4-Pack) King Dust & Allergy Control AC Furnace Filters MADE IN USA HVAC Pleated Electrostatic (Actual Size: 17.5 x 21 x .75)

WholesaleHVACDirect$38.400.0★0 rev

Filtrete 17x21x1 AC Furnace Air Filter MERV 8 MPR 700 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 4-Pack (Actual Size 16.69 x 20.69 x 0.81 in)

Filtrete$42.304.7★6,265 rev

Filter King 17x21x1 Air Filter (MERV 8) (4-Pack) Dust & Allergy Control AC Furnace Filters MADE IN USA HVAC Pleated Electrostatic (Actual Size: 17 x 21 x .75)

Filter King$38.634.7★1,569 rev

Newest

by launch date

WholesaleHVACDirect 17.5x21x1 Air Filter (MERV 8) (4-Pack) King Dust & Allergy Control AC Furnace Filters MADE IN USA HVAC Pleated Electrostatic (Actual Size: 17.5 x 21 x .75)

WholesaleHVACDirect$38.400 rev

2mo ago

Upgraded 17.5x21x1 MERV 13 furnace replacement filter household air conditioning and air conditioning HVAC filter replacement 6 pack

QCYZTL$75.135 rev

10mo ago

Glasfloss ZL 17.5x21x1 MERV 10 Pleated Air Filters. 5-Pack

Glasfloss$53.406 rev

1y ago

Filtrete 17x21x1 AC Furnace Air Filter MERV 8 MPR 700 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 4-Pack (Actual Size 16.69 x 20.69 x 0.81 in)

Filtrete$42.306,265 rev

2y ago

Filtrete 17.5x22x1 AC Furnace Air Filter MERV 8 MPR 700 Tough on Pollen Easy on Airflow 3-Month Pleated 1-Inch Electrostatic Air Cleaning Filter 4-Pack (Actual Size 17.19 x 21.69 x 0.81 in)

Filtrete$43.346,265 rev

2y ago

What buyers say about 17.5x21x1 air filter

What buyers praise and complain about, mined from review topics.

What buyers love

Size-Overall38%

“Fit well”

Quality-Overall25%

“Product Quality”

Compatibility-Overall13%

“Solid product and fit perfectly in my A/C”

Efficiency13%

“Works very good”

Filtration13%

“Always have a great experience with Filter King”

What buyers complain about

Filtration100%

“If it's not doing it's job, it's you, not the filter”

Top return reasons

Size-Overall87%

Compatibility-Overall7%

Filtration3%

Functionality-Overall2%

Advertised Vs Actual Product2%

Defective Material/Parts1%

Thickness0%

Common questions

Is 17.5x21x1 air filter profitable to sell on Amazon United States?: The niche generates $31K/yr across 8 tracked products. 0 of 2 products launched in the last 360 days are still selling. 90-day search growth is +24.4%. Flapen's verdict: Skip it (42/100).
How competitive is the 17.5x21x1 air filter niche?: 6 brands and 14 sellers compete. The top 5 products take 91% of clicks and top 5 brands hold 97% of demand.
What do buyers complain about in 17.5x21x1 air filter?: Top complaints mined from reviews: Filtration. The return rate is 0.7%.
What does it cost to enter the 17.5x21x1 air filter niche?: Listings span $38.40–$75.13; the average listing price is $49.40 (sweet spot $15–$100). The average incumbent carries 2,359 reviews — the moat a new listing must climb.