Is sea kelp profitable to sell on Amazon United States?

The niche generates $78K/yr across 8 tracked products. 90-day search growth is -15.6%. Flapen's verdict: Skip it (41/100).

How competitive is the sea kelp niche?

8 brands and 21 sellers compete. The top 5 products take 89% of clicks and top 5 brands hold 89% of demand.

What do buyers complain about in sea kelp?

Top complaints mined from reviews: Side Effects, Nutritional Content, Vitamin. The return rate is 0.0%.

When does demand for sea kelp peak?

Demand is steady year-round — the busiest month runs 1.4× the quietest.

What does it cost to enter the sea kelp niche?

Listings span $5.62–$33.84; the average listing price is $15.21 (sweet spot $15–$100). The average incumbent carries 2,281 reviews — the moat a new listing must climb.

sea kelp

Skip it

A concentrated shelf (top 5 take 89% of clicks) — this niche doesn't clear our bar today.

Returns

Incredible0.0%

return rate — above 5% kills the launch gate

Conversion

Incredible13.9%

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

Avg price

Great$15.21

avg listing price — sweet spot $15–$100

Price range

Good$5.62–$33.84

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

Review moat

Okay2,280.75

avg incumbent reviews — the moat a new listing must climb

Brand share

Okay89%

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

Quality gap

Bad4.7★

avg incumbent rating — lower means beatable quality

Market size

Bad$78K

$78K/yr · 37K searches

Growth

Bad-15.6%

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

Competition

Bad89%

top-5 click share — a locked-up shelf

According to Flapen's Amazon United States niche tracking, sea kelp is a $78K/yr Amazon United States market (37K searches/yr). The top 5 brands hold 89% of demand. Verdict: Skip it — 41/100.

Data updated Jul 28, 2026 · scored weekly · How we score niches

sea kelp market data

Units sold / yr: 4K–5K; avg 500–750/product
Revenue / yr: $61K–$76K; units × avg price
Conversion rate: 13.9%
Avg BSR: #611
Page quality: 0%
Prime: 100%
Sponsored: 75%
Out of stock: 0.0%
Avg brand age: 86 months
Avg seller age: 155 days

Competition & brand share

The top 5 products capture 89% of clicks — a locked-up shelf that new listings rarely crack.

Brands

8 flat

Sellers

Top-5 brand share

89%

Top 20: 100%

Top-5 click share

89%

Top 20: 100%

Open market

Dr. Berg Nutritionals52%
Carlyle17%
Zazzee8%
Triquetra Health6%
Life Extension6%
NOW Foods5%
Open — no brand owns it (2 brands, 6%)

Demand & seasonality

Weekly Amazon search volume, last 103 weeks — -15.6% search growth over the last 90 days.

No pronounced peak months · busiest ÷ quietest = 1.4×

Open Trend

Top sea kelp search terms

sea kelp iodine supplement16K/yr -16.3%10.1% conv.
seaweed supplement9K/yr -9.8%2.5% conv.
dr berg iodine4K/yr -15.7%14.1% conv.
dr berg sea kelp3K/yr -14.7%18.6% conv.
sea kelp iodine3K/yr -25.4%13.7% conv.
dr berg sea kelp enhanced iodine2K/yr -23.8%21.6% conv.

All search terms

Top sea kelp 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 8 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

Dr. Berg Sea Kelp Enhanced Iodine - 200 mcg of Premium Iodine - Seaweed Blend Includes Klamath Blue-Green Algae & Sea Kelp - 90 Capsules

Dr. Berg Nutritionals$33.844.8★612 rev

Carlyle Sea Kelp Iodine Supplement | 225mcg | 300 Tablets

Carlyle$10.294.6★2,128 rev

Zazzee USDA Organic Kelp Iodine 30:1 Extract 300 mcg per Capsule Vegan

Zazzee$19.404.6★52 rev

Organic Iodine Supplement from Sea Vegetable Complex Whole Food & Raw Form - Iodine Plus Trace Mineral Complex Contains Purest Icelandic Sea Kelp Irish Moss & Bladderwrack (250 mcg)

Triquetra Health$17.794.7★1,900 rev

Life Extension Sea-Iodine kelp and bladderwrack-derived Iodine Supports Healthy Levels of This Essential Nutrient for Thyroid Health and Beyond Non-GMO Gluten-Free Vegetarian 60 Capsules

Life Extension$5.624.6★8,248 rev

Newest

by launch date

Dr. Berg Sea Kelp Enhanced Iodine - 200 mcg of Premium Iodine - Seaweed Blend Includes Klamath Blue-Green Algae & Sea Kelp - 90 Capsules

Dr. Berg Nutritionals$33.84612 rev

2y ago

Organic Iodine Supplement from Sea Vegetable Complex Whole Food & Raw Form - Iodine Plus Trace Mineral Complex Contains Purest Icelandic Sea Kelp Irish Moss & Bladderwrack (250 mcg)

Triquetra Health$17.791,900 rev

3y ago

Zazzee USDA Organic Kelp Iodine 30:1 Extract 300 mcg per Capsule Vegan

Zazzee$19.4052 rev

4y ago

Carlyle Sea Kelp Iodine Supplement | 225mcg | 300 Tablets

Carlyle$10.292,128 rev

4y ago

Nutricost Kelp Tablets 325mcg of Iodine 240 Tablets Gluten-Free

Nutricost$11.83743 rev

5y ago

What buyers say about sea kelp

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

What buyers love

Quality-Overall18%

“It is a quality capsule”

Efficiency7%

“Wonderful and effective”

Value For Money7%

“Reasonably priced”

Hormonal Balance6%

“Bonus: sea kelp helps with managing estrogen too so it is a must have for women who are dealing with hormone fluctuations”

Ease Of Chewing/Swallowing6%

“Easy to swallow”

Nutritional Content5%

“Overall, they seem to be reasonably well-made supplement pills”

Advertised Vs Actual Product5%

“was as advertised”

Vitamin5%

“It is a good supplement for me”

Vegan/Organic5%

“Good quality clean organic”

Energy Level4%

“seems to help me with energy”

What buyers complain about

Side Effects7%

“BECAUSE I STARTED FEELING MOODY, DEPRESSED AND EMOTIONAL, CRYING FOR NO GOOD REASON”

Nutritional Content5%

“Just know, if you're healthy and you take this you MAY NOT be healthy after a few days”

Vitamin4%

“The daily dose of iodine of 325 mcg per capsule is too high and not healthy”

Value For Money4%

“could be more competitively priced”

Visibility3%

“Didnt see a difference”

Certifications3%

“Company doesnt provide coa/heavy metal testing”

Allergies3%

“he said I am having an allergic reaction to something”

Size-Overall3%

“The capsules are small”

Salt Content2%

“Unfortunately, I dont eat a lot of salt and I tend to use sea salt, which doesnt have added iodine”

Dosage2%

“Only thing to be aware of is the dosage is on the higher side for some people”

Top return reasons

Moist/Dry100%

Common questions

Is sea kelp profitable to sell on Amazon United States?: The niche generates $78K/yr across 8 tracked products. 90-day search growth is -15.6%. Flapen's verdict: Skip it (41/100).
How competitive is the sea kelp niche?: 8 brands and 21 sellers compete. The top 5 products take 89% of clicks and top 5 brands hold 89% of demand.
What do buyers complain about in sea kelp?: Top complaints mined from reviews: Side Effects, Nutritional Content, Vitamin. The return rate is 0.0%.
When does demand for sea kelp peak?: Demand is steady year-round — the busiest month runs 1.4× the quietest.
What does it cost to enter the sea kelp niche?: Listings span $5.62–$33.84; the average listing price is $15.21 (sweet spot $15–$100). The average incumbent carries 2,281 reviews — the moat a new listing must climb.