Size 4 Swim Diapers Market Report: Sales Volume, Market Share, Leading Brands & Market Trends
Size 4 Swim Diapers sales on Amazon US totaled 260,100 units in July 2026 (▼ 20.5% vs. the prior month), generating an estimated $5,986,108 in revenue across the 50 top-ranked ASINs for this search term. Demand is heavily concentrated at the top of the ranking — the ten best performers capture 57.7% of unit volume and 57.9% of revenue, while a typical listing is priced at $21.08. The keyword itself pulled 3,915 Amazon queries over the same period (▼ 53.5% MoM).
Zooming out to the 12-month window ending July 2026, the size 4 swim diapers Top 50 moved 1,999,100 units and $58,937,565 in cumulative sales — an average of 166,592 units and $4,911,464 per month. Monthly throughput topped out at 327,000 units in June 2026 and dipped to 117,000 in December 2025, leaving the latest reading 56.5% higher than August 2025.
Size 4 Swim Diapers Sales Trend (Trailing 12 Months)
Based on the top 50 ASINs by monthly sales for this keyword
2025/08
2025/09
2025/10
2025/11
2025/12
2026/01
2026/02
2026/03
2026/04
2026/05
2026/06
2026/07
Monthly Sales 2026/07
260.1K
▼ 20.5% MoM
Monthly Revenue 2026/07
$6M
▼ 14.0% MoM
Top 10 Market Share 2026/07
57.7%
Size 4 Swim Diapers Market Share & Sales Concentration on Amazon US — July 2026
The most-sold size 4 swim diapers listing on Amazon US in July 2026 is ASIN B0795WF49L (Brand: Pampers), which sold 30,000 units at $9.97 apiece — equal to 11.5% of every unit tracked in this report.
The Top 10 ASINs account for 150,000 units and $3,468,300 in July 2026 — 57.7% of unit volume and 57.9% of revenue among all 50 ranked ASINs in this report.
Sales Volume of Top ASINs for 'Size 4 Swim Diapers' on Amazon
July 2026
Is 57.7% Top 10 share highly concentrated?
Ask AI to evaluate competition, market structure, and entry opportunities using ’s tracked Amazon sales, ranking, and keyword data.
Powered by ASINSIGHT MCP · Grounded in ASINSIGHT Amazon data
Top 5 Volume Share breakdown
B0795WF49L
Pampers Swim Diapers - Splashers - Size 4, 18 Count, Gap-Free Disposable Baby Swimming Pants
30K
▼ 25.0%vs. prior month
$299.1K
latest month
12-month trend
B0795W29GC
Pampers Splashers Swim Diapers, Size 5, 17 Count, Disposable Swim Diapers, Contains Mess, No Swell
30K
▲ 0.0%vs. prior month
$299.1K
latest month
12-month trend
B07DC8BR3B
Pampers Swaddlers Diapers, Size 4 (15-34 lbs), 150 Count, Fragrance Free, Hypoallergenic, Absorbent, Pediatrician Recommended, Skin Safe
20K
▲ 0.0%vs. prior month
$995.4K
latest month
12-month trend
B00394DQGE
Huggies Little Swimmers Swim Diapers Size 4, 18 Count | Doesn’t Swell in Water, Helps Contain Mess, Refastenable Sides, Hypoallergenic & Dermatologist-Tested, Fun Designs
10K
▲ 0.0%vs. prior month
$99.9K
latest month
12-month trend
B00394DQGO
HUGGIES Little Swimmers Swim Diapers Size 5-6, 17 Count
10K
▼ 50.0%vs. prior month
$99.9K
latest month
12-month trend
B07961T2MS
Pampers Swim Diapers - Splashers - Size 2-3, 20 Count, Gap-Free Disposable Baby Swimming Pants
10K
▼ 66.7%vs. prior month
$99.7K
latest month
12-month trend
Unlock to view all Top 50 ASIN competitors and their sales contributions
Best Size 4 Swim Diapers Brands on Amazon US — Top 2 Brand Sales Concentration (July 2026)
Pampers is the best-performing size 4 swim diapers brand in July 2026, moving 120,000 units across 7 ASINs for 80.0% of Top 10 volume. HUGGIES follows with 30,000 units (20.0%).
With 2 brands splitting the Top 10 and 100.0% of volume sitting with three of them, this is a concentrated shelf — the leaders hold multiple listings or one very high-velocity ASIN, so a new entrant competes against established review moats rather than an open field. Average selling prices among the leaders run from $23.99 to $26.34, which frames the price band a competing listing has to justify.
Brand share of Top 10 volume
Pampers
7 ASINs in Top 10
80.0%
Units
120K
Revenue
$2.7M
Avg. price
$26.34
B0795WF49L
$9.97·★4.7·31.5K revsPampers Swim Diapers - Splashers - Size 4, 18 Count, Gap-Free Disposable Baby Swimming Pants
Units sold30KB0795W29GC
$9.97·★4.7·31.5K revsPampers Splashers Swim Diapers, Size 5, 17 Count, Disposable Swim Diapers, Contains Mess, No Swell
Units sold30KB07DC8BR3B
$49.77·★4.8·129.6K revsPampers Swaddlers Diapers, Size 4 (15-34 lbs), 150 Count, Fragrance Free, Hypoallergenic, Absorbent, Pediatrician Recommended, Skin Safe
Units sold20KB07961T2MS
$9.97·★4.7·31.5K revsPampers Swim Diapers - Splashers - Size 2-3, 20 Count, Gap-Free Disposable Baby Swimming Pants
Units sold10KB07LFQ9CXC
$44.99·★4.8·129.6K revsPampers Swaddlers Diapers, Size 4 (15-34 lbs), 120 Count, Fragrance Free, Hypoallergenic, Absorbent, Pediatrician Recommended, Skin Safe
Units sold10KB08W9G2JCX
$49.77·★4.7·27.6K revsPampers Diapers - Cruisers 360 - Size 4, 144 Count, Babyproof up to 100% Leakproof Pull-On Diaper
Units sold10KB0GMS6LJ93
$9.94·★4.7·31.5K revsPampers Splashers Swim Diapers, Size 6+, 15 Count, Disposable Swim Diapers, Contains Mess, No Swell
Units sold10K
HUGGIES
3 ASINs in Top 10
20.0%
Units
30K
Revenue
$727.8K
Avg. price
$23.99
B00394DQGE
$9.99·★4.8·33.8K revsHuggies Little Swimmers Swim Diapers Size 4, 18 Count | Doesn’t Swell in Water, Helps Contain Mess, Refastenable Sides, Hypoallergenic & Dermatologist-Tested, Fun Designs
Units sold10KB00394DQGO
$9.99·★4.8·33.7K revsHUGGIES Little Swimmers Swim Diapers Size 5-6, 17 Count
Units sold10KB0DKYRHL2Y
$51.99·★4.8·46.8K revsHuggies Little Movers Diapers Size 4, 150 Count (6 Packs of 25) | Double Grip Strips, Blowout Protection, Secure Flexible Fit, Up to 12-Hour Protection, Dry Touch Liner, Wetness Indicator
Units sold10K
Trending Size 4 Swim Diapers Products — Growth Leaders & New Top 10 Entrants
Based on July 2026 data, this shortlist surfaces the two kinds of ASIN worth keeping an eye on — the ones that just broke into the Top 10, and the ones growing fastest month over month. On the growth side, B07DKRWKGY leads positive momentum with ▲ 100.0% MoM growth on 200 units, with B07VFNZMLX close behind at ▲ 50.0% MoM on 3K units.
The two signals carry different weight. A fresh entrant means share has already changed hands — an incumbent gave up its place to make room, so any competitive set drawn up a month ago is now out of date. A steep growth rate works as the earlier warning: it marks demand that is still compounding, usually a month or two before the ranking catches up to it.
B07DKRWKGY
Pampers Splashers Size 4-5 9-15 kg Disposable Swim Diapers for Optimal Protection in Water, 11 Pieces
Price
$15.54
Rating
4.7
Reviews
7.8K
Latest month sales
B07VFNZMLX
Luvs Size 4 Baby Diapers, Platinum Protection Bluey Diapers for Day & Night, Size 4, 144 Count (Packaging May Vary)
Price
$30.99
Rating
4.5
Reviews
20.7K
Latest month sales
B0028FKM1M
Pampers Diapers - Baby Dry - Size 4, 28 Count, Absorbent Disposable Infant Diaper (Packaging May Vary)
Unlock to view ASIN details and product titles
Price
$9.97
Rating
4.7
Reviews
96.7K
Latest month sales
One Amazon dataset. Two ways to use it.
Every number in this size 4 swim diapers report comes from the Amazon market data ASINSIGHT tracks. Pick how you want to work with it.
Explore the full data
Browse the complete, structured picture in a ready-made interface — and keep tracking it as the market moves.
- Organic vs. ad traffic shifts per product
- Hourly rank and search-volume tracking
- Competitor ASINs and historical trends
Starts with a free ASINSIGHT account
Analyze the data your way
Connect the same data to ChatGPT, Claude or Cursor, then combine any dimensions to answer your own questions.
- Combine product, keyword, sales & ranking data freely
- Follow up in your own words, no fixed reports
- Works in ChatGPT, Claude & Cursor
20,000 credits/mo free, no credit card