v3.26.1
Earnings (Loss) Per Share - Calculation of Basic and Diluted Net Loss Per Share (Details) - USD ($)
$ / shares in Units, $ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Numerator        
Net loss $ (1,836) $ 1,787 $ (4,026) $ (1,520)
Less: Net income (loss) attributable to noncontrolling interests (1,725) 1,497 (3,460) (620)
Net loss attributable to Viant Technology Inc. (111) 290 (566) (900)
Add back: Reallocation of net income (loss) attributable to noncontrolling interest from the assumed exchange of RSUs and NQSOs for Class A common stock 0 90 0 0
Income tax benefit (expense) from the assumed exchange of dilutive securities for Class A common stock 0 (24) 0 0
Net income (loss) attributable to Viant Technology, Inc.—diluted $ (1,836) $ 356 $ (4,026) $ (900)
Weighted-average shares of Class A common stock outstanding:        
Weighted-average shares of Class A common stock outstanding—basic (shares) 19,695,000 15,996,000 18,767,000 16,216,000
Weighted-average shares of Class A common stock outstanding—diluted (shares) 65,193,000 19,903,000 64,328,000 16,216,000
Basic (USD per share) $ (0.01) $ 0.02 $ (0.03) $ (0.06)
Diluted (USD per share) $ (0.03) $ 0.02 $ (0.06) $ (0.06)
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 12,175,000 46,696,000 12,175,000 56,523,000
Class A Common Stock        
Weighted-average shares of Class A common stock outstanding:        
Weighted-average shares of Class A common stock outstanding—basic (shares) 19,695,000 15,996,000 18,767,000 16,216,000
Weighted-average shares of Class A common stock outstanding—diluted (shares) 65,193,000 19,903,000 64,328,000 16,216,000
Class B Common Stock        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 45,498,000 46,696,000 45,561,000 46,696,000
Restricted Stock Units        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 7,506,000 0 7,506,000 5,058,000
Restricted Stock Units | Class A Common Stock        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 0 1,497,000 0 0
Nonqualified Stock Options        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 4,182,000 0 4,182,000 4,769,000
Nonqualified Stock Options | Class A Common Stock        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 0 2,410,000 0 0
Performance Shares        
Anti-dilutive shares excluded from loss per share of Class A common stock—diluted:        
Total shares excluded from loss per share of Class A common stock—diluted (shares) 487,000 0 487,000 0