Net Loss per Share - Schedule of Earning Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Earnings Per Share [Abstract]
Net loss attributable to GitLab, Basic	$ (155,138)	$ (192,194)	$ (130,741)
Net loss attributable to GitLab, Diluted	$ (155,138)	$ (192,194)	$ (130,741)
Weighted-average shares used to compute net loss per share attributable to GitLab Class A and Class B common stockholders, basic	79,755,000	50,343,000	47,308,000
Weighted-average shares used to compute net loss per share attributable to GitLab Class A and Class B common stockholders, diluted	79,755,000	50,343,000	47,308,000
Net loss per share attributable to GitLab Class A and Class B common stockholders, basic	$ (1.95)	$ (3.82)	$ (2.76)
Net loss per share attributable to GitLab Class A and Class B common stockholders, diluted	$ (1.95)	$ (3.82)	$ (2.76)