Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2019	Nov. 12, 2019
Cover page.
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2019
Document Transition Report	false
Entity File Number	000-55264
Entity Registrant Name	DYADIC INTERNATIONAL, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	45-0486747
Entity Address, Address Line One	140 Intracoastal Pointe Drive
Entity Address, Address Line Two	Suite 404
Entity Address, City or Town	Jupiter
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33477
City Area Code	561
Local Phone Number	743-8333
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
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	DYAI
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		27,213,157
Entity Central Index Key	0001213809
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Amendment Flag	false