Net Loss per Share - Schedule of Earning Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2023	Jul. 31, 2022
Earnings Per Share [Abstract]
Net loss attributable to GitLab, basic	$ (50,080)	$ (59,024)	$ (102,549)	$ (85,123)
Net loss attributable to GitLab, diluted	$ (50,080)	$ (59,024)	$ (102,549)	$ (85,123)
Weighted-average shares used to compute net loss per share attributable to GitLab Class A and Class B common stockholders, basic (in shares)	153,644,000	147,797,000	152,683,000	147,248,000
Weighted-average shares used to compute net loss per share attributable to GitLab Class A and Class B common stockholders, diluted (in shares)	153,644,000	147,797,000	152,683,000	147,248,000
Net loss per share attributable to GitLab Class A and Class B common stockholders, basic (in USD per share)	$ (0.33)	$ (0.40)	$ (0.67)	$ (0.58)
Net loss per share attributable to GitLab Class A and Class B common stockholders, diluted (in USD per share)	$ (0.33)	$ (0.40)	$ (0.67)	$ (0.58)