Cover - shares	3 Months Ended
	Jun. 30, 2023	Oct. 16, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2023
Current Fiscal Year End Date	--03-31
Entity File Number	033-17773-NY
Entity Registrant Name	ROCKETFUEL BLOCKCHAIN, INC.
Entity Central Index Key	0000823546
Entity Tax Identification Number	90-1188745
Entity Incorporation, State or Country Code	NV
Entity Address, Address Line One	201 Spear Street
Entity Address, Address Line Two	Suite 1100
Entity Address, City or Town	San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94105
City Area Code	(424)
Local Phone Number	256-8560
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Elected Not To Use the Extended Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		35,604,890