Joint Venture - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2025	Oct. 31, 2024	Oct. 31, 2025	Oct. 31, 2024
Noncontrolling Interest [Line Items]
Total stock-based compensation expense (gain)	$ 51,682	$ 48,042	$ 161,793	$ 139,263
GitLab Information Technology (Hubei) Co., LTD ("JiHu")
Noncontrolling Interest [Line Items]
Total stock-based compensation expense (gain)	700	$ 1,000	1,400	$ (800)
Compensation expense not yet recognized	$ 4,200		$ 4,200
Period for recognition (in years)			2 years 7 months 6 days
GitLab Information Technology (Hubei) Co., LTD ("JiHu")
Noncontrolling Interest [Line Items]
Ownership percentage	54.00%	54.00%	54.00%	54.00%

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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