Mk4
Worth a lookShows low returns (0.1%), but strong incumbent ratings (4.6★) keeps it on the watch list.
Returns
Incredible0.1%return rate — above 5% kills the launch gate
Avg price
Incredible$31.62avg listing price — sweet spot $15–$100
Price range
Great$9.70–$73.59cheapest to priciest tracked listing — scored on the share inside $15–$100
Conversion
Great9.4%search→purchase rate — share of searches ending in a sale
Market size
Okay$262K$262K/yr · 88K searches
Brand share
Okay80%top-5 brand share — brands hold most of the demand
Review moat
Okay2,452.38avg incumbent reviews — the moat a new listing must climb
Growth
Okay+0.4%90-day search growth — must beat 0% to launch
Competition
Okay70%top-5 click share — a locked-up shelf
Quality gap
Bad4.6★avg incumbent rating — lower means beatable quality
Is mk4 profitable on Amazon?
According to Flapen's Amazon United States niche tracking, mk4 is a $262K/yr Amazon United States market (88K searches/yr). The top 5 brands hold 80% of demand. Verdict: Worth a look — 51/100.
Data updated Jul 29, 2026 · scored weekly · How we score niches
mk4 market size & sales
Units sold, revenue, conversion and listing quality across the tracked shelf.- Units sold / yr
- 8K–10K
- avg 500–750/product
- Revenue / yr
- $253K–$316K
- units × avg price
- Conversion rate
- 9.4%
- Avg BSR
- #483
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 100%
- Out of stock
- 0.0%
- Avg brand age
- 74 months
- Avg seller age
- 158 days
Competition: brands, sellers & click share
The top 5 products capture 70% of clicks — a locked-up shelf that new listings rarely crack.Brands
13 falling
Sellers
42
Top-5 brand share
80%
Top 20: 100%
Top-5 click share
70%
Top 20: 100%
Open market
16%
- Life Extension52%
- Nutricost11%
- Carlson7%
- THORNE5%
- NOW Foods5%
- InnovixLabs4%
- Open — no brand owns it (7 brands, 16%)
mk4 demand & seasonality
Weekly Amazon search volume, last 102 weeks — +0.4% search growth over the last 90 days.No pronounced peak months · busiest ÷ quietest = 1.6×
Top mk4 search terms shoppers use
The exact queries shoppers type, with yearly volume, growth and conversion.- mk419K/yr
- vitamin k2 mk416K/yr
- k2 mk411K/yr
- life extension k211K/yr
- mk4 vitamin k26K/yr
- life extension vitamin k25K/yr
- life extension mega k24K/yr
- mk-44K/yr
- life extension k2 mk73K/yr
- mega k23K/yr
Top mk4 products & what they sell for
Every tracked product — its share of the shelf, its review moat, and what it sells for.Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
All 16 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Life Extension Mega Vitamin K2 High Potency for Strong Bones clinically Studied 45 mg K2 Dosage Promotes Healthy Bone Density Gluten-Free Non-GMO 30 Capsules
Life Extension$25.464.7★812 rev
Nutricost Vitamin K2 (MK4) 240 Capsules (100mcg) - Gluten Free and Non-GMO
Nutricost$14.614.7★4,626 rev
Life Extension Super K Vitamin K Supplement 2000 Mcg Vitamin K and 1180 Mcg Vitamin K2 Heart Health Once-Daily 90 Softgels
Life Extension$19.394.6★6,990 rev
Life Extension Low Dose Vitamin K2 Supports Arterial Health Non-GMO Gluten-Free 90 Softgels
Life Extension$11.114.7★1,829 rev
Carlson - Vitamin K2 MK-4 (Menatetrenone) Vitamin K Supplement Bone & Heart Health K2 Vitamin Soy-free 60 capsules
Carlson$20.514.8★796 rev
Newest
by launch date
NBI Osteo-MK4 60 Capsules
NBI$65.4239 rev
Super Vitamin K Complex (K2 MK7 + MK4 & K1) 360 Coconut Oil Softgles | Easily Absorbed K Vitamins Active Menaquinone Complex | Non-GMO
Micro Ingredients$24.60444 rev
Carlyle Vitamin K2 Supplement 100 mcg | K2 MK-4 | 240 Capsules
Carlyle$10.001,269 rev
TACNEX OC/Mace Spray Holster for Duty Belt Pepper Spray Pouch MK3 MK4 Canister Holder Nylon Carry Case w/Top Flap Copper Snap MOLLE Strap for Police Security LE (Tall Nylon Pouch MK-4 and Similar)
TACNEX$13.79292 rev
Life Extension Mega Vitamin K2 High Potency for Strong Bones clinically Studied 45 mg K2 Dosage Promotes Healthy Bone Density Gluten-Free Non-GMO 30 Capsules
Life Extension$25.46812 rev
Trending
90-day click momentum
AOR Peak K2 Vitamin K2 MK-4 90 Vegan Capsules 30-90 Day Supply Essential for Bone Structure
AOR$43.214.6★
TACNEX OC/Mace Spray Holster for Duty Belt Pepper Spray Pouch MK3 MK4 Canister Holder Nylon Carry Case w/Top Flap Copper Snap MOLLE Strap for Police Security LE (Tall Nylon Pouch MK-4 and Similar)
TACNEX$13.794.2★
THORNE - Vitamin K2 - Concentrated Vitamin K2 (as MK-4) Liquid Supplement - Supports Bone Heart & and Blood Vessel Health* - Third-Party Certified - Gluten Dairy & Soy-Free - 1 Fl Oz
THORNE$73.594.4★
InnovixLabs Full Spectrum Vitamin K2-90 Softgels with 600 mcg of Trans Form MK7 and MK4 - Supports General Health and Bone Strength - Soy and Gluten Free K2 Vitamin Supplement
InnovixLabs$26.234.7★
Life Extension Mega Vitamin K2 High Potency for Strong Bones clinically Studied 45 mg K2 Dosage Promotes Healthy Bone Density Gluten-Free Non-GMO 30 Capsules
Life Extension$25.464.7★
What reviews say buyers love and hate about mk4
What buyers praise and complain about, mined from review topics.What buyers love
“Great Product, Fills a real need”
“Great Vitamins”
“Good value for money”
“Easy to swallow”
“Totally satisfied taking this with my calcium”
“Well-dosed and easy to integrate into daily supplements”
“Very beneficial for heart health”
“Good for bones”
“As described”
“Great supplement I use this every morning and the dosage and size is perfect”
What buyers complain about
“Low dose is harder to find”
“dangerous amount of Vitamin K. Now I am stuck with it since it cant be returned”
“The pills are larger”
“Just a little more cost”
“Need better quality control”
“had a bad feeling round my chest when I took this it went away”
“some find it causes digestive issues”
“eventually lots of vomiting”
“Extremely misleading here”
“this product formulation needs to be revised”
Top return reasons
Common mk4 questions
- Is mk4 profitable to sell on Amazon United States?
- The niche generates $262K/yr across 16 tracked products. 90-day search growth is +0.4%. Flapen's verdict: Worth a look (51/100).
- How competitive is the mk4 niche?
- 13 brands and 42 sellers compete. The top 5 products take 70% of clicks and top 5 brands hold 80% of demand.
- What do buyers complain about in mk4?
- Top complaints mined from reviews: Dosage, Vitamin, Size-Overall. The return rate is 0.1%.
- When does demand for mk4 peak?
- Demand is steady year-round — the busiest month runs 1.6× the quietest.
- What does it cost to enter the mk4 niche?
- Listings span $9.70–$73.59; the average listing price is $31.62 (sweet spot $15–$100). The average incumbent carries 2,452 reviews — the moat a new listing must climb.