v3.23.1
Income taxes - Effective tax rate reconciliation (Details)
12 Months Ended
Jan. 31, 2023
Jan. 31, 2022
Jan. 31, 2021
Income Tax Disclosure [Abstract]      
Federal income tax benefit at statutory rate (as a percent) 21.00% 21.00% 21.00%
State and local tax, net of federal benefit (as a percent) 5.00% 9.00% 10.00%
Permanent differences (as a percent) 0.00% 0.00% 0.00%
Equity compensation (as a percent) 0.00% 6.00% 44.00%
Foreign taxes (as a percent) 0.00% 0.00% 0.00%
Other (as a percent) 0.00% 0.00% (4.00%)
Change in valuation allowance (as a percent) (26.00%) (36.00%) (71.00%)
Effective income tax rate (as a percent) 0.30% 0.20% (0.20%)