Document and Entity Information - shares	3 Months Ended
	Oct. 31, 2017	Dec. 12, 2017
Document And Entity Information
Entity Registrant Name	PURE BIOSCIENCE, INC.
Entity Central Index Key	0001006028
Document Type	10-Q
Document Period End Date	Oct. 31, 2017
Amendment Flag	false
Current Fiscal Year End Date	--07-31
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		67,981,861
Trading Symbol	PURE
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2018