Net (Loss) Income Per Share Attributable to Common Stockholders - Schedule of Anti-Dilutive Common Stock Equivalents Excluded from Computation of Diluted Net (Loss) Income Per Share (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2021	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020
Class A Common Stock
Total weighted-average anti-dilutive common stock equivalents	41,047	359,425	187,769	357,283
Class A Common Stock | Convertible preferred stock
Total weighted-average anti-dilutive common stock equivalents	0	285,145	137,074	283,643
Class A Common Stock | Unvested RSUs
Total weighted-average anti-dilutive common stock equivalents	19,445	30,675	27,675	28,673
Class A Common Stock | Outstanding stock options
Total weighted-average anti-dilutive common stock equivalents	19,560	43,039	20,860	44,539
Class A Common Stock | Shares subject to repurchase from RSAs and early exercised stock options
Total weighted-average anti-dilutive common stock equivalents	1,663	566	1,967	428
Class A Common Stock | Shares issuable under 2021 ESPP
Total weighted-average anti-dilutive common stock equivalents	379	0	193	0
Class B Common Stock
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0
Class B Common Stock | Convertible preferred stock
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0
Class B Common Stock | Unvested RSUs
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0
Class B Common Stock | Outstanding stock options
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0
Class B Common Stock | Shares subject to repurchase from RSAs and early exercised stock options
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0
Class B Common Stock | Shares issuable under 2021 ESPP
Total weighted-average anti-dilutive common stock equivalents	0	0	0	0