filling knife
Skip itPricing outside the sweet spot ($6.14 avg) — this niche doesn't clear our bar today.
Returns
Incredible0.3%return rate — above 5% kills the launch gate
Conversion
Incredible14.2%search→purchase rate — share of searches ending in a sale
Brand share
Good74%top-5 brand share — brands hold most of the demand
Review moat
Okay1,634.78avg incumbent reviews — the moat a new listing must climb
Quality gap
Okay4.5★avg incumbent rating — lower means beatable quality
Market size
Okay£199K£199K/yr · 229K searches
Competition
Okay65%top-5 click share — leaders hold, buyers still browse
Price range
Okay£2.07–£21.16cheapest to priciest tracked listing — scored on the share inside $15–$100
Growth
Bad-12.5%90-day search growth — must beat 0% to launch
Avg price
Bad£6.14avg listing price — sweet spot $15–$100
According to Flapen's Amazon United Kingdom niche tracking, filling knife is a £199K/yr Amazon United Kingdom market (229K searches/yr). The top 5 brands hold 74% of demand. Verdict: Skip it — 48/100.
Data updated Jul 22, 2026 · scored weekly · How we score niches
filling knife market data
- Units sold / yr
- 30K–40K
- avg 2,000–2,500/product
- Revenue / yr
- £184K–£246K
- units × avg price
- Conversion rate
- 14.2%
- Avg BSR
- #15
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 33%
- Out of stock
- 5.0%
- Avg brand age
- 42 months
- Avg seller age
- 169 days
Competition & brand share
The top 5 products take 65% of clicks — established leaders, but buyers still shop beyond them.Brands
14 falling
Sellers
75
Top-5 brand share
74%
Top 20: 100%
Top-5 click share
65%
Top 20: 100%
Open market
22%
- Harris41%
- KZXXZH14%
- Axus Decor8%
- YWYHHM6%
- Sukudon5%
- G4GADGET4%
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -12.5% search growth over the last 90 days.No pronounced peak months · busiest ÷ quietest = 1.6×
Top filling knife search terms
- filling knife78K/yr
- filler knife43K/yr
- filler tool27K/yr
- filling knife set21K/yr
- wall filler tool9K/yr
- filling knives10K/yr
- flexible filling knife6K/yr
- filler scraper5K/yr
- filler knife for walls5K/yr
- filling blades5K/yr
Top filling knife 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
Harris Seriously Good Continental Filling Knives 4 Pack 102064328
Harris£2.314.6★3,920 rev
KZXXZH Wallpaper Scrapers 1.5 3 4 5 Wide Putty Knife Set Metal Spackle Knives Paint Tools for Wallpaper/Decals/Drywall Finishing/Plaster Scraping (4 Pack)
KZXXZH£5.384.5★2,887 rev
Harris Trade Filling Knife 2
Harris£4.014.6★106 rev
7 Piece Stainless Steel Wallpaper Scraper and Paint Tool Set With Filling Knives Spackle Drywall Joint Filler Putty Knife for Plastering Walls - Includes Tool Bag Hand Tools Gifts for Men
YWYHHM£12.454.3★139 rev
Sukudon 4 Pieces shankless Blade Painting Tools Seriously Good Continental Filling Knives (45MM+65MM+85MM+105MM)
Sukudon£4.934.4★262 rev
Newest
by launch date
G4GADGET Wallpaper Scraper 3 Inch Stainless Steel Paint & Putty Scraper with Soft Grip Handle Heavy Duty DIY Scraper Tool for Wallpaper Steamer Removal Drywall Filler Glass/Window & Hob Cleaning
G4GADGET£3.338 rev
ZAVIA Continental Filling Knives Pack of 4 | Flexible Filling Knife | Stainless Steel Filler Spreader | Filling Knife Set for Holes Cracks & Walls | Filler Knife with Plastic Grip (Standard)
ZAVIA£3.4029 rev
WINICE Paint Scraper Set 4 Pack Stainless Steel Putty Knives (2 4 6 8) with Soft Grip Handle Wallpaper Remover & Plastering Tools for Drywall Paint and Wall Repair
WINICE£8.9682 rev
DEKEones 5 PCS Wallpaper Scrapers Set Stainless Steel Wall Filler Scrapers Strippers Remover 4 Paint Scrapers and 1 Multi Scraper Tool Filling Paint Stripper for Drywall Decals (1 3 4 6 10)
DEKEones£11.763,406 rev
Harris Trade Filling Knife 2
Harris£4.01106 rev
Trending
90-day click momentumG4GADGET Wallpaper Scraper 3 Inch Stainless Steel Paint & Putty Scraper with Soft Grip Handle Heavy Duty DIY Scraper Tool for Wallpaper Steamer Removal Drywall Filler Glass/Window & Hob Cleaning
G4GADGET£3.334.4★
WINICE Paint Scraper Set 4 Pack Stainless Steel Putty Knives (2 4 6 8) with Soft Grip Handle Wallpaper Remover & Plastering Tools for Drywall Paint and Wall Repair
WINICE£8.964.4★
Axus Decor Pro-Fill (Blue Series) Stainless Steel Flexible Filling Knife Filler Knife - Putty Knife for Professional & DIY Projects - Anti Rust Blade and Rubberized Handle - 2 Inch/ 50mm
Axus Decor£4.964.7★
ZAVIA Continental Filling Knives Pack of 4 | Flexible Filling Knife | Stainless Steel Filler Spreader | Filling Knife Set for Holes Cracks & Walls | Filler Knife with Plastic Grip (Standard)
ZAVIA£3.404.2★
Sukudon 4 Pieces shankless Blade Painting Tools Seriously Good Continental Filling Knives (45MM+65MM+85MM+105MM)
Sukudon£4.934.4★
What buyers say about filling knife
What buyers praise and complain about, mined from review topics.What buyers love
“Excellent product”
“Good price”
“works as it should”
“Comes in handy”
“Great variety of sizes”
“clean up well after use”
“durability is very good”
“Comfortable grip handel”
“not flimsy”
“get the job done without bending”
What buyers complain about
“I know theyre cheap”
“not as robust as they look”
“expensive for just a small bit of plastic”
“leaves to bigger bead”
“Unfortunately this item came filthy as if it was already used”
“Very thin and cheaply made”
“One of the handles was faulty”
“However, they begin to rust as soon as they come into contact with water”
“Couldn't use it”
“didn't do as advertised”
Top return reasons
Common questions
- Is filling knife profitable to sell on Amazon United Kingdom?
- The niche generates £199K/yr across 18 tracked products. 1 of 2 products launched in the last 360 days are still selling. 90-day search growth is -12.5%. Flapen's verdict: Skip it (48/100).
- How competitive is the filling knife niche?
- 14 brands and 75 sellers compete. The top 5 products take 65% of clicks and top 5 brands hold 74% of demand.
- What do buyers complain about in filling knife?
- Top complaints mined from reviews: Quality-Overall, Strength, Value For Money. The return rate is 0.3%.
- When does demand for filling knife peak?
- Demand is steady year-round — the busiest month runs 1.6× the quietest.
- What does it cost to enter the filling knife niche?
- Listings span £2.07–£21.16; the average listing price is £6.14 (sweet spot $15–$100). The average incumbent carries 1,635 reviews — the moat a new listing must climb.