CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenue	$ 42,629	$ 40,144
Operating expenses:
Platform operations	26,194	24,344
Sales and marketing	13,756	14,185
Technology and development	5,003	5,900
General and administrative	11,083	10,420
Total operating expenses	56,036	54,849
Loss from operations	(13,407)	(14,705)
Interest expense, net	152	235
Other expense (income), net	4	(70)
Total other expense, net	156	165
Net loss	(13,563)	(14,870)
Less: Net loss attributable to noncontrolling interests	(10,371)	(11,766)
Net loss attributable to Viant Technology Inc.	$ (3,192)	$ (3,104)
Loss per share of Class A common stock:
Basic	$ (0.23)	$ (0.27)
Diluted	$ (0.23)	$ (0.27)
Weighted-average shares of Class A common stock outstanding:
Basic	13,809	11,500
Diluted	13,809	11,500