Cover - shares	9 Months Ended
	Jul. 31, 2025	Sep. 19, 2025
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jul. 31, 2025
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2025
Current Fiscal Year End Date	--10-31
Entity File Number	000-56709
Entity Registrant Name	GMTECH INC.
Entity Central Index Key	0002000762
Entity Tax Identification Number	93-3955846
Entity Incorporation, State or Country Code	WY
Entity Address, Address Line One	Room 1534, 15/F., Star House
Entity Address, Address Line Two	No.3 Salisbury Road
Entity Address, Address Line Three	Tsim Sha Tsui
Entity Address, City or Town	Kowloon
Entity Address, Country	HK
Entity Address, Postal Zip Code	0000
City Area Code	852
Local Phone Number	36195831
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	true
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		12,000,000