Risks and Concentration - Customers And Vendors Concentration (Details)	6 Months Ended		12 Months Ended
	Sep. 30, 2025 item customer	Sep. 30, 2024 customer item	Mar. 31, 2025 item customer
Customer concentration risk \| Total revenues \| Non-related party
Risks and Concentration
Number of customers	3	3
Customer concentration risk \| Total revenues \| Non-related party \| Customer one
Risks and Concentration
Concentration risk percentage (in %)	26.80%	22.40%
Customer concentration risk \| Total revenues \| Non-related party \| Customer two
Risks and Concentration
Concentration risk percentage (in %)	19.50%	19.70%
Customer concentration risk \| Total revenues \| Non-related party \| Customer three
Risks and Concentration
Concentration risk percentage (in %)	12.90%	16.80%
Customer concentration risk \| Total revenues \| Related party
Risks and Concentration
Number of customers	1	1
Customer concentration risk \| Total revenues \| Related party \| Customer one
Risks and Concentration
Concentration risk percentage (in %)	28.60%	27.40%
Customer concentration risk \| Total accounts receivable
Risks and Concentration
Number of customers	3		4
Customer concentration risk \| Total accounts receivable \| Customer one
Risks and Concentration
Concentration risk percentage (in %)	27.50%		31.00%
Customer concentration risk \| Total accounts receivable \| Customer two
Risks and Concentration
Concentration risk percentage (in %)	18.20%		26.30%
Customer concentration risk \| Total accounts receivable \| Customer three
Risks and Concentration
Concentration risk percentage (in %)	13.10%		22.80%
Customer concentration risk \| Total accounts receivable \| Customer four
Risks and Concentration
Concentration risk percentage (in %)			15.10%
Customer concentration risk \| Total accounts receivable \| Related party
Risks and Concentration
Number of customers	1
Customer concentration risk \| Total accounts receivable \| Related party \| Customer one
Risks and Concentration
Concentration risk percentage (in %)	26.10%
Vendor concentration risk \| Total purchases
Risks and Concentration
Number of vendors \| item	3	4
Vendor concentration risk \| Total purchases \| Vendor one
Risks and Concentration
Concentration risk percentage (in %)	31.40%	21.80%
Vendor concentration risk \| Total purchases \| Vendor two
Risks and Concentration
Concentration risk percentage (in %)	27.10%	21.80%
Vendor concentration risk \| Total purchases \| Vendor three
Risks and Concentration
Concentration risk percentage (in %)	13.80%	14.10%
Vendor concentration risk \| Total purchases \| Vendor four
Risks and Concentration
Concentration risk percentage (in %)		11.30%
Vendor concentration risk \| Total advances to vendors
Risks and Concentration
Number of vendors \| item	3		2
Vendor concentration risk \| Total advances to vendors \| Vendor one
Risks and Concentration
Concentration risk percentage (in %)	38.00%		44.90%
Vendor concentration risk \| Total advances to vendors \| Vendor two
Risks and Concentration
Concentration risk percentage (in %)	36.70%		39.60%
Vendor concentration risk \| Total advances to vendors \| Vendor three
Risks and Concentration
Concentration risk percentage (in %)	25.00%

YSX Tech Co., Ltd 6-K