vitamin d3 4000 iu
Skip itA deep review moat (90,576 avg reviews) — this niche doesn't clear our bar today.
Returns
Incredible0.0%return rate — above 5% kills the launch gate
Conversion
Incredible12.8%search→purchase rate — share of searches ending in a sale
Avg price
Good$14.35avg listing price — sweet spot $15–$100
Price range
Good$5.76–$34.10cheapest to priciest tracked listing — scored on the share inside $15–$100
Market size
Okay$171K$171K/yr · 93K searches
Growth
Bad-0.7%90-day search growth — must beat 0% to launch
Quality gap
Bad4.7★avg incumbent rating — lower means beatable quality
Competition
Bad84%top-5 click share — a locked-up shelf
Brand share
Bad97%top-5 brand share — brand-locked demand
Review moat
Bad90,575.7avg incumbent reviews — the moat a new listing must climb
According to Flapen's Amazon United States niche tracking, vitamin d3 4000 iu is a $171K/yr Amazon United States market (93K searches/yr). The top 5 brands hold 97% of demand. Verdict: Skip it — 40/100.
Data updated Aug 5, 2026 · scored weekly · How we score niches
vitamin d3 4000 iu market data
- Units sold / yr
- 13K–15K
- avg 1,500–2,000/product
- Revenue / yr
- $179K–$215K
- units × avg price
- Conversion rate
- 12.8%
- Avg BSR
- #92
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 80%
- Out of stock
- 0.0%
- Avg brand age
- 92 months
- Avg seller age
- 164 days
Competition & brand share
The top 5 products capture 84% of clicks — a locked-up shelf that new listings rarely crack.Brands
6 flat
Sellers
69
Top-5 brand share
97%
Top 20: 100%
Top-5 click share
84%
Top 20: 100%
Open market
0%
- NatureWise74%
- Nature Made8%
- WeightWorld8%
- Sports Research5%
- Pure Encapsulations3%
- YounGlo Research3%
Demand & seasonality
Weekly Amazon search volume, last 101 weeks — -0.7% search growth over the last 90 days.No pronounced peak months · busiest ÷ quietest = 1.4×
Top vitamin d3 4000 iu search terms
- vitamin d3 4000 iu33K/yr
- vitamin d 4000 iu31K/yr
- vitamin d 400010K/yr
- vitamin d3 4000 iu softgels7K/yr
- d3 4000 iu7K/yr
- vitamin d3 40005K/yr
Top vitamin d3 4000 iu 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.
All 10 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
NatureWise Vitamin D3 4000 IU Supplement Immune Support 360 Mini Softgels
NatureWise$14.954.7★195,696 rev
NatureWise Vitamin D3 4000 IU Supplement Immune Support 90 Mini Softgels
NatureWise$8.654.7★195,696 rev
WeightWorld Vitamin D3 4000 IU (100mcg) for Bone Strength Muscle Health & Immune Support | 400 Days Supply | Vegan D3 Vitamin (Cholecalciferol) from Lichen | 400 VIT D3 Tablets Non-GMO Gluten-Free
WeightWorld$15.594.6★23,887 rev
Sports Research Vitamin D3 4000iu/100mcg with Coconut MCT Oil 360 Count
Sports Research$16.794.4★104 rev
NatureWise Vitamin D3 4000 IU Supplement Immune Support 200 Mini Softgels
NatureWise$11.314.7★195,696 rev
Newest
by launch dateSports Research Vitamin D3 4000iu/100mcg with Coconut MCT Oil 360 Count
Sports Research$16.79104 rev
NatureWise Vitamin D3 4000 IU Supplement Immune Support 90 Mini Softgels
NatureWise$8.65195,696 rev
NatureWise Vitamin D3 4000 IU Supplement Immune Support 200 Mini Softgels
NatureWise$11.31195,696 rev
NatureWise Vitamin D3 4000 IU Supplement Immune Support 30 Mini Softgels
NatureWise$5.76195,696 rev
Pure Encapsulations Vitamin D3 & K2 120 Capsules
Pure Encapsulations$34.105,090 rev
Trending
90-day click momentumWeightWorld Vitamin D3 4000 IU (100mcg) for Bone Strength Muscle Health & Immune Support | 400 Days Supply | Vegan D3 Vitamin (Cholecalciferol) from Lichen | 400 VIT D3 Tablets Non-GMO Gluten-Free
WeightWorld$15.594.6★
Pure Encapsulations Vitamin D3 & K2 120 Capsules
Pure Encapsulations$34.104.8★
Nature Made Vitamin D3 2000 IU (50 mcg) 250 Vitamin D Softgels
Nature Made$12.904.8★
NatureWise Vitamin D3 4000 IU Supplement Immune Support 90 Mini Softgels
NatureWise$8.654.7★
NatureWise Vitamin D3 4000 IU Supplement Immune Support 360 Mini Softgels
NatureWise$14.954.7★
What buyers say about vitamin d3 4000 iu
What buyers praise and complain about, mined from review topics.What buyers love
“the quality has been consistent with every purchase”
“Best vitamins”
“Good price”
“Ease swallow”
“easy to use”
“As described”
“Good Results”
“perfect vitamin d dosing”
“Clean ingredients”
“Excellent supplement”
What buyers complain about
“which makes it harder for my body to process certain vitamins”
“Small capsule size”
“I had a reaction starting with this high of a dose”
“No taste”
“These have a strong FISH odor”
“Plastic used is low quality and brittle, especially the cap”
“costly”
“after researching, it said that high of a dose could become toxic”
“nausea and weird stomach pain”
“This is my 2nd bottle I purchased that the cap breakd”
Top return reasons
Common questions
- Is vitamin d3 4000 iu profitable to sell on Amazon United States?
- The niche generates $171K/yr across 10 tracked products. 90-day search growth is -0.7%. Flapen's verdict: Skip it (40/100).
- How competitive is the vitamin d3 4000 iu niche?
- 6 brands and 69 sellers compete. The top 5 products take 84% of clicks and top 5 brands hold 97% of demand.
- What do buyers complain about in vitamin d3 4000 iu?
- Top complaints mined from reviews: Vitamin, Size-Overall, Allergies. The return rate is 0.0%.
- When does demand for vitamin d3 4000 iu peak?
- Demand is steady year-round — the busiest month runs 1.4× the quietest.
- What does it cost to enter the vitamin d3 4000 iu niche?
- Listings span $5.76–$34.10; the average listing price is $14.35 (sweet spot $15–$100). The average incumbent carries 90,576 reviews — the moat a new listing must climb.