Earnings Per Share (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share Reconciliation [Abstract]
Net income attributable to Karat Packaging Inc.	$ 3,786,000	$ 4,072,000	$ 15,149,000	$ 16,595,000
Weighted average number of common shares in issue (in shares)	19,710,043	15,180,879	17,945,205	15,185,440
Basic earnings per share (in dollars per share)	$ 0.19	$ 0.27	$ 0.84	$ 1.09
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Net income attributable to Karat Packaging Inc.	$ 3,786,000	$ 4,072,000	$ 15,149,000	$ 16,595,000
Weighted average common shares outstanding, basic (in shares)	19,710,043	15,180,879	17,945,205	15,185,440
Dilutive shares
Stock options and restricted stock units (in shares)	171,252	271,000	164,922	271,000
Adjusted weighted average number of common shares (in shares)	19,881,295	15,451,879	18,110,127	15,456,440
Diluted earnings per share (in dollars per share)	$ 0.19	$ 0.26	$ 0.84	$ 1.07
Potentially dilutive shares excluded from diluted earnings per share calculation (in shares)			89,828