coolant refractometer
Skip itSoft demand (-21.8% this quarter) — this niche doesn't clear our bar today.
Avg price
Incredible$39.45avg listing price — sweet spot $15–$100
Review moat
Great259.67avg incumbent reviews — the moat a new listing must climb
Returns
Great1.5%return rate — above 5% kills the launch gate
Conversion
Great8.0%search→purchase rate — share of searches ending in a sale
Price range
Good$11.18–$139.04cheapest to priciest tracked listing — scored on the share inside $15–$100
Brand share
Okay77%top-5 brand share — brands hold most of the demand
Quality gap
Okay4.5★avg incumbent rating — lower means beatable quality
Market size
Okay$169K$169K/yr · 54K searches
Competition
Okay67%top-5 click share — leaders hold, buyers still browse
Growth
Bad-21.8%90-day search growth — must beat 0% to launch
According to Flapen's Amazon United States niche tracking, coolant refractometer is a $169K/yr Amazon United States market (54K searches/yr). The top 5 brands hold 77% of demand. Verdict: Skip it — 49/100.
Data updated Jul 9, 2026 · scored weekly · How we score niches
coolant refractometer market data
- Units sold / yr
- 4K–5K
- avg 100–250/product
- Revenue / yr
- $158K–$197K
- units × avg price
- Conversion rate
- 8.0%
- Avg BSR
- #79
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 89%
- Out of stock
- 0.0%
- Avg brand age
- 72 months
- Avg seller age
- 175 days
Competition & brand share
The top 5 products take 67% of clicks — established leaders, but buyers still shop beyond them.Brands
15 rising
Sellers
60
Top-5 brand share
77%
Top 20: 100%
Top-5 click share
67%
Top 20: 100%
Open market
20%
- aichose50%
- TRZ12%
- Performance Tool6%
- OTC5%
- AMTAST4%
- Anbachi4%
Demand
Weekly Amazon search volume, last 35 weeks — -21.8% search growth over the last 90 days.Top coolant refractometer search terms
- coolant refractometer11K/yr
- def refractometer11K/yr
- def tester8K/yr
- glycol refractometer7K/yr
- refractometer coolant4K/yr
- def fluid tester5K/yr
- antifreeze refractometer4K/yr
- glycol tester3K/yr
Top coolant refractometer 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 18 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
4-in-1 DEF Antifreeze Coolant Refractometer for Automobile Antifreeze System Diesel Exhaust Fluid Battery Acid and Windshield Washer Fluid
aichose$21.474.6★1,345 rev
DEF Refractometer for Measuring Diesel Exhaust Fluid Concentration of Diesel Engines
aichose$23.674.6★731 rev
TRZ 4-in-1 Antifreeze Refractometer Ethylene Glycol Propylene Glycol in Antifreeze Freezing Point Temperature and Concentration AdBlue DEF and Industrial Battery Fluid
TRZ$22.324.6★460 rev
3-in-1 Antifreeze Tester in Fahrenheit Scale for Checking Freezing Point and Concentration of Ethylene Glycol or Propylene Glycol Based Automobile Antifreeze Coolant Also for Battery Acid Condition
aichose$21.564.6★297 rev
OTC 5025 Diesel Exhaust Fluid (DEF) Refractometer Kit - Includes Refractometer Dropper Lens Wipe Cloth Instructions and Quick Start Guide Screwdriver and Case
OTC$117.694.8★356 rev
Newest
by launch date
5-in-1 Refractometer for DEF Urea Concentration Windshield Washer & PG/EG Antifreeze Freeze Point Battery Specific Gravity - Refractometer for Coolant Antifreeze and Diesel Fluid
HyVisTek$20.0624 rev
Antifreeze Refractometer Antifreeze Coolant Tester for Checking Antifreeze Freezing Point Concentration of Ethylene Glycol & Propylene Glycol Battery Acid Condition Windshield Washer Fluid
UHANBUT$11.183 rev
4-in-1 Refractometer for Ethylene & Propylene Glycol Antifreeze DEF Battery Acid & Windshield Fluid Accurate ATC Tester with C Scale for Coolant Freezing Point & SRFI Automotive & Industrial Use
PUREFIZ$19.5516 rev
5-in-1 DEF Antifreeze Refractometer Coolant Tester with ATC Hydrometer Kit for Automotive Antifreeze Diesel Exhaust Fluid Ethylene Glycol or Propylene Glycol Based Windshield Washer Fluid Battery Acid
NEEBETEK$21.7246 rev
BRWISSEN Digital Refractometer 5-in-1 Antifreeze Coolant Diesel Exhaust Fluid DEF Tester - Urea Concentration Antifreeze & Car Windshield Washer Fluid Freeze Point Detector
BRWISSEN$139.0410 rev
Trending
90-day click momentum
Performance Tool W80158 Multifunction Refractometer - Brix Scale Measures DEF Ethylene Glycol Propylene Glycol Battery Fluid Anti-Freeze Brewing Beer Making Wine and More
Performance Tool$59.414.8★
Antifreeze Refractometer Antifreeze Coolant Tester for Checking Antifreeze Freezing Point Concentration of Ethylene Glycol & Propylene Glycol Battery Acid Condition Windshield Washer Fluid
UHANBUT$11.184.3★
AMTAST DEF Refractometer 0-40% AdBlue Diesel Exhaust Fluid Urea Concentration Refractometer Hand Held Refractometer with ATC for Automotive Diesel Made of Copper Not Cheap Aluminum (Model AMR001)
AMTAST$25.574.6★
Antifreeze Refractometer VRESOURCING Hand-Held Anti Freeze Tester for Car Coolant Adblue Antifreeze System Glycol Propylene Glycol Ethylene Battery Acid Coolant Windshield Fluid
V·RESOURCING$15.094.4★
BRWISSEN Digital Refractometer 5-in-1 Antifreeze Coolant Diesel Exhaust Fluid DEF Tester - Urea Concentration Antifreeze & Car Windshield Washer Fluid Freeze Point Detector
BRWISSEN$139.044.8★
What buyers say about coolant refractometer
What buyers praise and complain about, mined from review topics.What buyers love
“Easy to use”
“Works great”
“good value”
“Good product”
“It works as advertised”
“the instructions are clear”
“Easy to operate an clean”
“An accurate easy-to-use device that makes it simple o check the strength of underhood fluids”
“it seems to be working great only wish they would have a freeze try to go along with it”
“I expect it to last a long time”
What buyers complain about
“box are very cheap”
“Others have found the instructions to be clear”
“your vehicle gets shut down”
“The readings are not standard and has no Celsius label. Not a standard refractometer”
“Carry Case hard to open”
“May have been a return”
“But in this case the protective plastic was around the display”
Top return reasons
Common questions
- Is coolant refractometer profitable to sell on Amazon United States?
- The niche generates $169K/yr across 18 tracked products. 0 of 1 products launched in the last 360 days are still selling. 90-day search growth is -21.8%. Flapen's verdict: Skip it (49/100).
- How competitive is the coolant refractometer niche?
- 15 brands and 60 sellers compete. The top 5 products take 67% of clicks and top 5 brands hold 77% of demand.
- What do buyers complain about in coolant refractometer?
- Top complaints mined from reviews: Quality-Overall, Instructions/User Manual/Troubleshooting, Maintenance And Repair. The return rate is 1.5%.
- What does it cost to enter the coolant refractometer niche?
- Listings span $11.18–$139.04; the average listing price is $39.45 (sweet spot $15–$100). The average incumbent carries 260 reviews — the moat a new listing must climb.