CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Additional Paid-In Capital	Accumulated Other Comprehensive Income	Accumulated Deficit	Class A and Class B Common Stock Class A and Class B Common Stock
Beginning balance (in shares) at Jan. 31, 2025					325,579,105
Beginning balance at Jan. 31, 2025	$ 1,669,247	$ 3,294,542	$ 2,158	$ (1,627,485)	$ 32
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)					3,199,972
Issuance of common stock upon exercise of stock options	15,229	15,229
Vesting of restricted stock units (in shares)					5,738,178
Vesting of restricted stock units	1				$ 1
Issuance of common stock under employee stock purchase plan (in shares)					578,154
Issuance of common stock under employee purchase plan	9,065	9,065
Cancellation of common stock in connection with acquisition (in shares)					(2,960,897)
Cancellation of common stock in connection with acquisition	(52,693)	(52,693)
Stock-based compensation	147,974	147,974
Other comprehensive income (loss)	(825)		(825)
Net loss	(280,212)			(280,212)
Ending balance (in shares) at Jul. 31, 2025					332,134,512
Ending balance at Jul. 31, 2025	1,507,786	3,414,117	1,333	(1,907,697)	$ 33
Beginning balance (in shares) at Apr. 30, 2025					331,072,169
Beginning balance at Apr. 30, 2025	1,546,542	3,378,134	4,053	(1,835,678)	$ 33
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)					678,982
Issuance of common stock upon exercise of stock options	2,952	2,952
Vesting of restricted stock units (in shares)					2,766,104
Issuance of common stock under employee stock purchase plan (in shares)					578,154
Issuance of common stock under employee purchase plan	9,065	9,065
Cancellation of common stock in connection with acquisition (in shares)					(2,960,897)
Cancellation of common stock in connection with acquisition	(52,693)	(52,693)
Stock-based compensation	76,659	76,659
Other comprehensive income (loss)	(2,720)		(2,720)
Net loss	(72,019)			(72,019)
Ending balance (in shares) at Jul. 31, 2025					332,134,512
Ending balance at Jul. 31, 2025	1,507,786	3,414,117	1,333	(1,907,697)	$ 33
Beginning balance (in shares) at Jan. 31, 2026					337,776,950
Beginning balance at Jan. 31, 2026	1,437,145	3,513,017	2,314	(2,078,220)	$ 34
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)					957,402
Issuance of common stock upon exercise of stock options	3,148	3,148
Vesting of restricted stock units (in shares)					6,721,361
Vesting of restricted stock units	1				$ 1
Issuance of common stock under employee stock purchase plan (in shares)					582,302
Issuance of common stock under employee purchase plan	7,512	7,512
Cancellation of common stock in connection with acquisition (in shares)					(1,952)
Cancellation of common stock in connection with acquisition	(37)	(37)
Stock-based compensation	172,237	172,237
Other comprehensive income (loss)	(1,938)		(1,938)
Net loss	(169,564)			(169,564)
Ending balance (in shares) at Jul. 31, 2026					346,036,063
Ending balance at Jul. 31, 2026	1,448,504	3,695,877	376	(2,247,784)	$ 35
Beginning balance (in shares) at Apr. 30, 2026					341,481,403
Beginning balance at Apr. 30, 2026	1,438,121	3,591,419	1,051	(2,154,384)	$ 35
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (in shares)					741,262
Issuance of common stock upon exercise of stock options	2,266	2,266
Vesting of restricted stock units (in shares)					3,231,096
Issuance of common stock under employee stock purchase plan (in shares)					582,302
Issuance of common stock under employee purchase plan	7,512	7,512
Stock-based compensation	94,680	94,680
Other comprehensive income (loss)	(675)		(675)
Net loss	(93,400)			(93,400)
Ending balance (in shares) at Jul. 31, 2026					346,036,063
Ending balance at Jul. 31, 2026	$ 1,448,504	$ 3,695,877	$ 376	$ (2,247,784)	$ 35