Stockholders' Equity and Equity Incentive Plans (Tables)

12 Months Ended

Jan. 31, 2022

Equity [Abstract]

Schedule of Stock by Class Reserved for Future Issuance

We have the following shares of Class A common stock reserved for future issuance:

	As of January 31,
	2022	2021
Stock options outstanding	6,195,205	9,239,504
RSUs outstanding	5,546,366	4,510,730
ESPP purchase rights outstanding	1,784,687	724,883
Remaining shares available for future issuance under the 2011 and 2019 plan	56,620,720	44,584,783
Remaining shares available for future issuance under the ESPP	10,685,867	9,648,574
Total shares of Class A common stock reserved	80,832,845	68,708,474

Summary of Stock Option Activity Under Equity Incentive Plan

A summary of stock option activity under our equity incentive plan and related information is as follows:

	Stock Options
	Outstanding Stock Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life (Years)	Aggregate Intrinsic Value
	(in thousands, except share, life and per share data)
Outstanding as of January 31, 2021	9,239,504	$	7.17	7.0	$	3,371,457
Exercised	(2,881,485)	$	5.00		$	842,989
Canceled/forfeited/expired	(162,814)	$	11.24
Outstanding as of January 31, 2022	6,195,205	$	8.08	6.0	$	905,744
Vested and expected to vest as of January 31, 2022	6,195,205	$	8.08	6.0	$	905,744
Exercisable as of January 31, 2022	4,898,249	$	5.72	5.9	$	727,701

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

The Black-Scholes assumptions used to value the employee options at the grant dates are as follows:

	Year Ended January 31, 2020
Expected term (years)	5.0 - 6.1
Expected volatility	49.9% - 53.2%
Risk-free interest rate	1.6% - 2.5%
Expected dividend yield	—

Summary of Restricted Stock Units (RSUs) Activity Under Equity Incentive Plan

A summary of RSU activity under our equity incentive plan and related information is as follows:

	RSUs
	Unvested RSUs	Weighted-Average Grant Date Fair Value Per Share
Unvested as of January 31, 2021	4,510,730	$	194.57
Granted	3,195,949	$	265.12
Vested	(1,768,702)	$	190.36
Canceled/forfeited	(391,611)	$	250.92
Unvested as of January 31, 2022	5,546,366	$	232.58

Summary of Assumptions for Estimating Fair Value of ESPP Purchase Rights

We estimated the fair value of ESPP purchase rights using a Black-Scholes option-pricing model with the following assumptions:

	Year Ended January 31,
	2022	2021
Expected term (years)	0.5 - 2.1	0.5 - 2.1
Expected volatility	40.3% - 75.0%	40.3% - 75.0%
Risk-free interest rate	0.0% - 2.5%	0.1% - 2.5%
Expected dividend yield	—	—

Summary of Stock-based Compensation Expense by Line Item

The stock-based compensation expense by line item in the accompanying consolidated statements of operations is summarized as follows:

	Year Ended January 31,
	2022		2021		2020
	(in thousands)
Cost of revenue	$	69,612	$	34,960	$	7,860
Research and development	113,000		50,161		11,645
Sales and marketing	229,297		146,377		41,465
General and administrative	65,378		44,320		12,139
Total stock-based compensation expense	477,287		275,818		73,109
Benefit from income taxes	(84,245)		—		—
Total stock-based compensation expense recorded to net income	$	393,042	$	275,818	$	73,109