v3.25.1

Stockholders' Equity - Summary of Stock Option Activity (Details) - Equity Incentive Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2025	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares, outstanding beginning balance	9,069,194
Number of shares, granted	2,201,259
Number of shares, forfeited	(1,091,697)
Number of shares, outstanding ending balance	10,178,756	9,069,194
Number of shares, exercisable	5,356,639
Number of shares, vested and expected to vest	10,178,756
Weighted-average exercise price, outstanding beginning balance	$ 10.55
Weighted-average exercise price, granted	2.45
Weighted-average exercise price, forfeited	5.93
Weighted-average exercise price, outstanding ending balance	13.36	$ 10.55
Weighted-average exercise price, exercisable	9.3
Weighted-average exercise price, vested and expected to vest	$ 9.3
Weighted-average remaining contractual term (in years), outstanding balance	5 years 9 months 18 days	7 years
Weighted-average remaining contractual term (in years), exercisable	4 years 2 months 12 days
Weighted-average remaining contractual term (in years), vested and expected to vest	5 years 9 months 18 days
Aggregate intrinsic value, outstanding balance	$ 27	$ 263
Aggregate intrinsic value, exercisable	21
Aggregate intrinsic value, vested and expected to vest	$ 27

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nkarta, Inc. 10-Q