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 BrilliA Inc
Entity Central Index Key 0002000230
Entity File Number 001-42410
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 51 Cuppage Road Unit #06-18
Entity Address, City or Town Singapore
Entity Address, Country SG
Entity Address, Postal Zip Code 229469
Entity Listings [Line Items]  
Title of 12(b) Security Class A Ordinary Shares, US$0.00005
Trading Symbol BRIA
Security Exchange Name NYSEAMER
Class A Ordinary Shares  
Entity Listings [Line Items]  
Entity Common Stock, Shares Outstanding 25,000,000
Class B Ordinary Shares  
Entity Listings [Line Items]  
Entity Common Stock, Shares Outstanding 5,625,000
Business Contact [Member]  
Entity Contact Personnel [Line Items]  
Contact Personnel Name Koh Wah Seng Philip
Contact Personnel Email Address philip.koh@brilliaincorporated.com
Entity Address, Address Line One 51 Cuppage Road Unit #06-18
Entity Address, City or Town Singapore
Entity Address, Country SG
Entity Address, Postal Zip Code 229469
Entity Phone Fax Numbers [Line Items]  
City Area Code +65
Local Phone Number 6235 3388