Cover - USD ($)	12 Months Ended
	Dec. 31, 2023	Apr. 16, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Dec. 31, 2023
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2023
Current Fiscal Year End Date	--12-31
Entity File Number	001-32698
Entity Registrant Name	MGT CAPITAL INVESTMENTS, INC.
Entity Central Index Key	0001001601
Entity Tax Identification Number	13-4148725
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	2076 Foster Mill Drive
Entity Address, City or Town	LaFayette
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30728
City Area Code	(914)
Local Phone Number	630–7430
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 3,456,493
Entity Common Stock, Shares Outstanding		943,170,903
ICFR Auditor Attestation Flag	false
Auditor Name	RBSM LLP
Auditor Location	Las Vegas, Nevada
Auditor Firm ID	587