Document and Entity Information (USD $)	12 Months Ended
	Sep. 30, 2012	Dec. 01, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	NEXT FUEL, INC.
Entity Central Index Key	0001422949
Amendment Flag	false
Current Fiscal Year End Date	--09-30
Document Type	10-K
Document Period End Date	Sep. 30, 2012
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2012
Entity Well-Known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Public Float	$ 10,631,129
Entity Common Stock, Shares Outstanding		10,972,500