v3.26.1
Cover
 12 Months Ended
Mar. 31, 2026
shares
Document Information [Line Items]  
Document Type 20-F
Document Registration Statement false
Document Annual Report true
Document Transition Report false
Document Financial Statement Error Correction [Flag] false
Document Shell Company Report false
Entity Interactive Data Current Yes
Document Accounting Standard International Financial Reporting Standards
ICFR Auditor Attestation Flag false
Amendment Flag false
Document Period End Date Mar. 31, 2026
Document Fiscal Year Focus 2026
Document Fiscal Period Focus FY
Entity Information [Line Items]  
Entity Registrant Name   CELLYAN BIOTECHNOLOGY CO., LTD  
Entity Central Index Key 0002007702
Entity File Number 001-42468
Entity Incorporation, State or Country Code E9
Current Fiscal Year End Date --03-31
Entity Well-known Seasoned Issuer No
Entity Voluntary Filers No
Entity Current Reporting Status Yes
Entity Shell Company false
Entity Filer Category Non-accelerated Filer
Entity Emerging Growth Company true
Entity Ex Transition Period false
Entity Contact Personnel [Line Items]  
Entity Address, Address Line One Room B1, 5/F., Well Town Industrial Building
Entity Address, Address Line Two 13 Ko Fai Road
Entity Address, Address Line Three Yau Tong
Entity Address, City or Town Kowloon
Entity Address, Country HK
Entity Address, Postal Zip Code 00000
Entity Listings [Line Items]  
Title of 12(b) Security Class A Ordinary Shares, par value $0.001 per share
Trading Symbol HKPD
Security Exchange Name NASDAQ
Entity Common Stock, Shares Outstanding 16,349,986
Business Contact [Member]  
Entity Contact Personnel [Line Items]  
Contact Personnel Name Chenyu Liang
Contact Personnel Email Address andy@cell-yan.com
Entity Address, Address Line One Room B1, 5/F., Well Town Industrial Building
Entity Address, Address Line Two 13 Ko Fai Road
Entity Address, Address Line Three Yau Tong
Entity Address, City or Town Kowloon
Entity Address, Country HK
Entity Address, Postal Zip Code 00000
Entity Phone Fax Numbers [Line Items]  
City Area Code +852
Local Phone Number 2618-9289