Document And Entity Information - shares	9 Months Ended
	Jan. 31, 2018	Mar. 16, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jan. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3
Entity Registrant Name	CHAMPIONS ONCOLOGY, INC.
Entity Central Index Key	0000771856
Current Fiscal Year End Date	--04-30
Entity Filer Category	Smaller Reporting Company
Trading Symbol	CSBR
Entity Common Stock, Shares Outstanding		11,000,847