Document And Entity Information - shares	9 Months Ended
	Jan. 31, 2021	Mar. 10, 2021
Document Information Line Items
Entity Registrant Name	FREQUENCY ELECTRONICS INC
Document Type	10-Q
Current Fiscal Year End Date	--04-30
Entity Common Stock, Shares Outstanding		9,199,625
Amendment Flag	false
Entity Central Index Key	0000039020
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Jan. 31, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Interactive Data Current	Yes