Net Loss Per Share Attributable To Common Stockholders - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Numerator:
Net loss	$ (271,101)	$ (117,573)	$ (76,567)
Denominator:
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic (in shares)	174,051,203	35,482,444	32,712,350
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, diluted (in shares)	174,051,203	35,482,444	32,712,350
Net loss per share attributable to Class A and Class B common stockholders, basic (in USD per share)	$ (1.56)	$ (3.31)	$ (2.34)
Net loss per share attributable to Class A and Class B common stockholders, diluted (in USD per share)	$ (1.56)	$ (3.31)	$ (2.34)
Class A and Class B Common Stock
Denominator:
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic (in shares)	174,051,203	35,482,444
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, diluted (in shares)	174,051,203	35,482,444
Net loss per share attributable to Class A and Class B common stockholders, basic (in USD per share)	$ (1.56)	$ (3.31)
Net loss per share attributable to Class A and Class B common stockholders, diluted (in USD per share)	$ (1.56)	$ (3.31)