Is casein protein powder profitable to sell on Amazon United States?

The niche generates $2.8M/yr across 30 tracked products. 90-day search growth is -1.6%. Flapen's verdict: Worth a look (63/100).

How competitive is the casein protein powder niche?

15 brands and 39 sellers compete. The top 5 products take 49% of clicks and top 5 brands hold 87% of demand.

What do buyers complain about in casein protein powder?

Top complaints mined from reviews: Taste-Overall, Texture/Consistency-Overall, Flavor. The return rate is 0.0%.

When does demand for casein protein powder peak?

Demand is steady year-round — the busiest month runs 1.5× the quietest.

What does it cost to enter the casein protein powder niche?

Listings span $22.36–$99.33; the average listing price is $54.59 (sweet spot $15–$100). The average incumbent carries 2,155 reviews — the moat a new listing must climb.

casein protein powder

Worth a look

Shows low returns (0.0%), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Returns

Incredible0.0%

return rate — above 5% kills the launch gate

Market size

Incredible$2.8M

$2.8M/yr · 979K searches

Price range

Incredible$22.36–$99.33

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

Avg price

Great$54.59

avg listing price — sweet spot $15–$100

Conversion

Good5.1%

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

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Competition

Good49%

top-5 click share — leaders hold, buyers still browse

Review moat

Okay2,154.93

avg incumbent reviews — the moat a new listing must climb

Brand share

Okay87%

top-5 brand share — brands hold most of the demand

Growth

Bad-1.6%

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

Signals High Price

According to Flapen's Amazon United States niche tracking, casein protein powder is a $2.8M/yr Amazon United States market (979K searches/yr). The top 5 brands hold 87% of demand. Verdict: Worth a look — 63/100.

Data updated Jul 10, 2026 · scored weekly · How we score niches

casein protein powder market data

Units sold / yr: 50K–60K; avg 1,500–2,000/product
Revenue / yr: $2.7M–$3.3M; units × avg price
Conversion rate: 5.1%
Avg BSR: #185
Page quality: 0%
Prime: 100%
Sponsored: 77%
Out of stock: 2.8%
Avg brand age: 83 months
Avg seller age: 143 days

Competition & brand share

The top 5 products take 49% of clicks — established leaders, but buyers still shop beyond them.

Brands

15 falling

Sellers

Top-5 brand share

87%

Top 20: 100%

Top-5 click share

49%

Top 20: 93%

Open market

10%

Optimum Nutrition33%
Nutricost28%
NAKED16%
Levels Nutrition7%
BulkSupplements4%
It's Just!3%
Open — no brand owns it (9 brands, 10%)

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -1.6% search growth over the last 90 days.

No pronounced peak months · busiest ÷ quietest = 1.5×

Open Trend

Top casein protein powder search terms

casein protein powder495K/yr +2.8%4.3% conv.
casein protein156K/yr -15.8%4.2% conv.
casein112K/yr -5.2%5.3% conv.
casein protein powder vanilla18K/yr +8.9%5.1% conv.
naked casein20K/yr +10.3%8.3% conv.
casein powder20K/yr -19.4%3.5% conv.
micellar casein protein powder21K/yr +4.7%4.4% conv.
casine protein powder17K/yr -4.2%4.7% conv.
protein powder casein15K/yr +5.5%4.0% conv.
micellar casein11K/yr +36.3%4.3% conv.

All search terms

Top casein protein powder 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★)

All 24 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Optimum Nutrition Gold Standard 100% Micellar Casein Protein Powder Slow Digesting Helps Keep You Full Overnight Muscle Recovery Chocolate Supreme 2 Pound (Packaging May Vary)

Optimum Nutrition$46.534.6★9,135 rev

NAKED Casein - 1Lb Micellar Casein Protein - Bulk Zero Carb NSF Certified GMO-Free Gluten Free Soy Free Preservative Free - Stimulate Muscle Growth - Enhance Recovery - 15 Servings

NAKED$24.964.4★2,077 rev

Nutricost Casein Protein Powder 2lb Vanilla - Micellar Casein Gluten Free Non-GMO

Nutricost$34.394.5★1,430 rev

Optimum Nutrition Gold Standard 100% Micellar Casein Protein Powder Slow Digesting Helps Keep You Full Overnight Muscle Recovery Creamy Vanilla 1.81 Pound (Packaging May Vary)

Optimum Nutrition$46.084.6★5,747 rev

Optimum Nutrition Gold Standard 100% Micellar Casein Protein Powder Slow Digesting Helps Keep You Full Overnight Muscle Recovery Chocolate Supreme 4 Pound (Packaging May Vary)

Optimum Nutrition$78.494.6★9,135 rev

Newest

by launch date

Its Just! - 100% Casein Protein Powder Made in USA One Ingredient Slow Burning Time Release (1 Pound (Pack of 1) Unflavored)

It's Just!$22.36326 rev

1y ago

Levels 100% Micellar Casein Protein Hormone Free Chocolate 2LB

Levels Nutrition$43.24458 rev

5y ago

Levels 100% Micellar Casein Protein Hormone Free Chocolate 4LB

Levels Nutrition$74.65458 rev

5y ago

Nutricost Casein Protein Powder 2lb Vanilla - Micellar Casein Gluten Free Non-GMO

Nutricost$34.391,430 rev

7y ago

Nutricost Casein Protein Powder 5lb Vanilla - Micellar Casein Gluten Free Non-GMO

Nutricost$65.131,430 rev

7y ago

What buyers say about casein protein powder

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

What buyers love

Taste-Overall26%

“Good taste”

Nutritional Content15%

“Great protein powder”

Flavor10%

“it also adds to the flavor”

Quality-Overall9%

“Excellent product”

Value For Money5%

“Worth it”

Blend/Ratio4%

“blends well,”

Solubility3%

“Simple to mix”

Sleep Quality2%

“Good for bedtime”

Muscle Pain Relief2%

“This stuff AAAA+ muscles stopped being so sore”

Ingredients-Overall2%

“clean in ingredients”

What buyers complain about

Taste-Overall20%

“Didnt taste good”

Texture/Consistency-Overall12%

“Weird texture”

Flavor7%

“The chocolate flavor is unacceptably weak”

Solubility5%

“Doesn't mix well”

Value For Money4%

“Total waste of money”

Sweetness4%

“Not overly sweet”

Nutritional Content3%

“this protein has been just awful”

Thickness3%

“Not thick”

Ease Of Chewing/Swallowing2%

“Cant drink it”

Advertised Vs Actual Product2%

“claiming that is not true”

Top return reasons

Ingredients-Overall100%

Common questions

Is casein protein powder profitable to sell on Amazon United States?: The niche generates $2.8M/yr across 30 tracked products. 90-day search growth is -1.6%. Flapen's verdict: Worth a look (63/100).
How competitive is the casein protein powder niche?: 15 brands and 39 sellers compete. The top 5 products take 49% of clicks and top 5 brands hold 87% of demand.
What do buyers complain about in casein protein powder?: Top complaints mined from reviews: Taste-Overall, Texture/Consistency-Overall, Flavor. The return rate is 0.0%.
When does demand for casein protein powder peak?: Demand is steady year-round — the busiest month runs 1.5× the quietest.
What does it cost to enter the casein protein powder niche?: Listings span $22.36–$99.33; the average listing price is $54.59 (sweet spot $15–$100). The average incumbent carries 2,155 reviews — the moat a new listing must climb.