Cover - USD ($)	12 Months Ended
	Sep. 30, 2025	Dec. 16, 2025	Mar. 31, 2025
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2025
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2025
Current Fiscal Year End Date	--09-30
Entity File Number	001-42044
Entity Registrant Name	NANO NUCLEAR ENERGY INC.
Entity Central Index Key	0001923891
Entity Tax Identification Number	88-0861977
Entity Incorporation, State or Country Code	NV
Entity Address, Address Line One	10 Times Square
Entity Address, Address Line Two	30th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10018
City Area Code	(212)
Local Phone Number	634-9206
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	NNE
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
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	false
Entity Shell Company	false
Entity Public Float			$ 703,834,174
Entity Common Stock, Shares Outstanding		50,474,294
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Auditor Firm ID	100
Auditor Name	WithumSmith+Brown, PC
Auditor Location	New York, New York