CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2021	Oct. 31, 2020
Income Statement [Abstract]
Revenue		$ 334,441	$ 159,624	$ 835,553	$ 401,584
Cost of revenue		120,786	66,681	324,253	159,684
Gross profit		213,655	92,943	511,300	241,900
Operating expenses:
Sales and marketing		190,971	134,727	540,678	325,267
Research and development		115,900	74,138	343,783	143,949
General and administrative		64,055	53,532	189,846	116,224
Total operating expenses		370,926	262,397	1,074,307	585,440
Operating loss		(157,271)	(169,454)	(563,007)	(343,540)
Interest income		1,985	1,517	6,787	5,654
Other income (expense), net		1,609	(519)	9,867	(1,561)
Loss before income taxes		(153,677)	(168,456)	(546,353)	(339,447)
Provision for income taxes		1,179	433	1,442	720
Net loss		$ (154,856)	$ (168,889)	$ (547,795)	$ (340,167)
Net loss per share attributable to Class A and Class B common stockholders - basic (in dollars per share)	[1]	$ (0.51)	$ (1.01)	$ (1.84)	$ (3.63)
Net loss per share attributable to Class A and Class B common stockholders - diluted (in dollars per share)	[1]	$ (0.51)	$ (1.01)	$ (1.84)	$ (3.63)
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders - basic (in shares)	[1]	303,006,685	166,868,200	297,435,637	93,763,599
Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders - diluted (in shares)	[1]	303,006,685	166,868,200	297,435,637	93,763,599

[1] On March 1, 2021, all shares of the Company’s then-outstanding Class B common stock were automatically converted into the same number of shares of Class A common stock, pursuant to the terms of the Company’s amended and restated certificate of incorporation. No additional shares of Class B common stock will be issued following such conversion. See Note 11 for further details.