Cover - USD ($)	12 Months Ended
	Aug. 31, 2020	Nov. 16, 2020	Feb. 29, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Transition Report	false
Document Period End Date	Aug. 31, 2020
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2020
Current Fiscal Year End Date	--08-31
Entity File Number	001-32046
Entity Registrant Name	Simulations Plus, Inc.
Entity Central Index Key	0001023459
Entity Tax Identification Number	95-4595609
Entity Incorporation, State or Country Code	CA
Entity Address, Address Line One	42505 Tenth Street West
Entity Address, City or Town	Lancaster
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	93534-7059
City Area Code	(661)
Local Phone Number	723-7723
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	SLP
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
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			$ 412,688,004
Entity Common Stock, Shares Outstanding		19,931,709