Quick answer: By the seamless knitting machines they publish: Tianpai Knitting (Yiwu) states nearly 1,000 Santoni machines and 350,000 pieces a day; JASAN Group states more than 150 Santoni machines at its Shaoxing base and about 300 in Vietnam, with capacity for 55 million seamless pieces a year group-wide; Yesseam (Xiamen) runs 50 Santoni machines; and Aolafree (Shenzhen) runs 40. The biggest plants suit the biggest programmes; neither of the top two states a minimum order quantity on the pages we reviewed.
How we ranked them
By the number of seamless knitting machines each company states on its own website, counting every site it names. Output figures are shown where they are published, but they are not used for the ranking: one factory counts per day, another per month or per year, and some include subcontractors. Factories that make seamless but publish no machine count were not ranked — Sansansun in Dongguan, for example, runs a dedicated seamless factory but gives no figure.
The ranking
1. Tianpai Knitting (Yiwu, Zhejiang) — nearly 1,000 machines
Tianpai states that it runs nearly 1,000 Santoni electronic jacquard machines, with a daily capacity of 350,000 pieces, and that its output value passed RMB 1 billion in 2023. It has thousands of employees and a production base in Cambodia. Its main line is high-end seamless underwear, alongside sportswear, swimwear and shapewear. Its website is in Chinese. Best for: very large seamless underwear and shapewear programmes.
2. JASAN Group (Hangzhou, with bases in Shaoxing, Guizhou and Vietnam) — about 450 machines published
Founded in 1994 and listed on China’s A-share main board, JASAN makes socks and seamless apparel. It states more than 150 Santoni seamless machines at its Shaoxing base, rated at more than 9 million seamless pieces a year, and about 300 Santoni machines at its plant in Hung Yen, Vietnam, rated at 32 million a year. Its Guizhou seamless plant, rated at 12 million pieces a year, has no machine count published. Group-wide, it states around 10,000 employees and capacity for 55 million seamless pieces a year. Best for: very large programmes, and brands that want production in Vietnam as well as China.
3. Yesseam (Xiamen, Fujian) — 50 machines
Yesseam runs 50 Santoni seamless machines, mainly the SM8-TOP2V, in 28G and 32G gauges, with cylinder diameters from 17 to 21 inches. Cutting and sewing run in the same factory, including 40 four-needle six-thread flatlock, 40 overlock and 45 single-needle lockstitch machines. Minimums are 50 pieces per style plain, 100 with your logo and 500 for full custom. Best for: brands launching or growing a seamless line in runs of hundreds rather than hundreds of thousands.
4. Aolafree (Shenzhen, Guangdong) — 40 machines
Aolafree states 40 Santoni seamless machines in a 3,000 m² seamless workshop. Its about page gives a monthly capacity of 400,000 pieces across its own sewing lines and more than 100 affiliated outsourcing plants; its homepage gives more than 300,000 pieces a month. Its site shows a minimum of 300 pieces per style, and 200 per colour for private label. Best for: mid-size seamless and sewn programmes.
The four side by side
| Rank | Factory | Seamless bases | Seamless machines published | Output published |
|---|---|---|---|---|
| 1 | Tianpai Knitting | Yiwu (plus a Cambodia base) | Nearly 1,000 Santoni | 350,000 pieces a day |
| 2 | JASAN Group | Shaoxing, Guizhou, Hung Yen (Vietnam) | 150+ Santoni (Shaoxing) + about 300 Santoni (Vietnam) | Capacity for 55 million seamless pieces a year, group-wide |
| 3 | Yesseam | Xiamen | 50 Santoni (SM8-TOP2V; 28G and 32G; 17–21″ cylinders) | Not published |
| 4 | Aolafree | Shenzhen | 40 Santoni | 300,000–400,000 pieces a month (varies by page; includes affiliated plants) |
What a machine count does and doesn’t tell you
It tells you the ceiling. It does not tell you whether the machines suit your product: the gauge decides how fine the knit can be, and the cylinder diameter decides which body sizes a machine can knit, so a wide size range can need more than one diameter. Our guide to gauges and cylinder sizes explains both, and seamless machine brands compared covers the machines themselves. Nor does a count tell you whether a factory will schedule a small run. Neither of the two largest factories here states a minimum order quantity on the pages we reviewed, so ask before assuming that an opening run of a few hundred pieces fits their plan.
Where Yesseam fits, honestly
We are a fraction of the size of the top two. If you need hundreds of thousands of seamless pieces a month, a plant with hundreds of machines is the natural home. If you need runs from 50 pieces per style upward, with seamless and cut-and-sew from one factory and a machine list you can check on a video call, a 50-machine floor is built for that. On published minimums we rank higher: see low-MOQ activewear factories, ranked.
Sources
| Source | What it establishes here |
|---|---|
| Tianpai Knitting — about (Chinese) | Machines, daily capacity, main products, 2023 output value |
| JASAN Group — about | Founding, listing, employees, group seamless capacity |
| JASAN Group — seamless apparel | Santoni machines in Shaoxing and Vietnam; capacity by base |
| Yesseam — seamless manufacturing | Machine models, gauges, cylinders and sewing floor |
| Aolafree — about us | Santoni machines, seamless workshop, monthly capacity, 300-piece minimum |
| Aolafree — home | Monthly capacity on the homepage |
| Sansansun — about us | Dedicated seamless factory; no machine count published |
FAQ
Which seamless factory in China has the most knitting machines?
Of the factories that publish a machine count, Tianpai Knitting in Yiwu states nearly 1,000 Santoni electronic jacquard machines and a daily capacity of 350,000 pieces. JASAN Group states more than 150 Santoni machines at its Shaoxing base and about 300 at its plant in Vietnam.
How many seamless machines does Yesseam have?
50 Santoni seamless circular knitting machines, mainly the SM8-TOP2V, in 28G and 32G, with cylinder diameters from 17 to 21 inches. Cutting and sewing run in the same factory in Xiamen.
Does a bigger seamless factory mean better quality?
No. Machine count measures capacity, not quality. Quality depends on the yarn, the knit programme, finishing and inspection, and a large plant built around very large programmes may not be set up for small runs. Compare samples and written terms, not machine counts alone.
How many seamless machines does my order need?
For an opening run of a few hundred pieces per style, the machine count matters less than two other things: whether the factory will schedule a small run, and whether it has the gauge and cylinder sizes your size range needs. Ask which machines your style would run on.
What do 28G and 32G mean on a seamless machine?
They are machine gauges: the number of needles per inch around the cylinder. A 32G machine knits a finer, denser surface than a 28G one. Both are used for seamless activewear; the right one depends on the look and weight you want.