Document and Entity Information - shares	6 Months Ended
	Feb. 29, 2020	Apr. 03, 2020
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Amendment Flag	false
Document Period End Date	Feb. 29, 2020
Entity File Number	000-06936
Entity Registrant Name	WD-40 COMPANY
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-1797918
Entity Address, Address Line One	9715 Businesspark Avenue
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92131
City Area Code	619
Local Phone Number	275-1400
Title of 12(b) Security	Common stock, par value $0.001 per share
Trading Symbol	WDFC
Security Exchange Name	NASDAQ
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Entity Central Index Key	0000105132
Current Fiscal Year End Date	--08-31
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		13,668,439