Document And Entity Information - shares	3 Months Ended
	Mar. 31, 2023	May 05, 2023
Document Information Line Items
Entity Registrant Name	ALLEGRO MERGER CORP.
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		4,110,000
Amendment Flag	false
Entity Central Index Key	0001720025
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Period End Date	Mar. 31, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q1
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Shell Company	true
Entity Ex Transition Period	false
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-38581
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	82-2425125
Entity Address, Address Line One	777 Third Avenue
Entity Address, Address Line Two	37th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10017
City Area Code	(212)
Local Phone Number	319-7676
Entity Interactive Data Current	Yes