Basis of Presentation and Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2025
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements as of June 30, 2025 and for the three and six months ended June 30, 2025 and 2024 have been prepared in accordance with U.S. generally accepted accounting principle ("U.S. GAAP") for interim financial information and pursuant to Article 10 of Regulation S-X of the Securities Act of 1933, as amended. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. These unaudited condensed financial statements include only normal and recurring adjustments that the Company believes are necessary to fairly state the Company’s financial position and the results of its operations and cash flows for the periods presented. The results for the three and six months ended June 30, 2025 are not necessarily indicative of the results expected for the full year or any subsequent interim period. The condensed balance sheet as of December 31, 2024 has been derived from the audited financial statements at that date but does not include all disclosures required by U.S. GAAP for complete financial statements. Because all of the disclosures required by U.S. GAAP for complete financial statements are not included herein, these unaudited condensed financial statements and the notes accompanying them should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2024 and the notes accompanying them, contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024 filed by the Company with the SEC on March 26, 2025.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the Company’s financial statements and accompanying notes. On an ongoing basis, management evaluates its estimates, including, but not limited to, those related to clinical trial accruals, fair value of assets and liabilities, impairment of assets, leases, share-based compensation and income taxes. Management bases its estimates on historical experience, knowledge of current events and actions it may undertake in the future that management believes to be reasonable under the circumstances. Actual results may differ from these estimates and assumptions.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares and pre-funded warrants outstanding for the period, without consideration of potential dilutive securities. Pre-funded warrants are considered outstanding for the purposes of computing basic and diluted net loss per share because shares may be issued for little or no additional consideration and are fully vested and exercisable after the original issuance date of the pre-funded warrants. Diluted net loss per share is computed by dividing the net loss by the sum of the weighted average number of common shares and pre-funded warrants plus the potential dilutive effects of potential dilutive securities outstanding during the period. Potential dilutive securities are excluded from diluted earnings or loss per share if the effect of such inclusion is antidilutive. The Company’s potentially dilutive securities, which include unvested common stock, outstanding stock options and restricted stock units under the Company’s equity incentive plans, have been excluded from the computation of diluted net loss per share as they would be antidilutive to the net loss per share. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.
Long-Lived Asset Impairment	Long-Lived Asset Impairment The Company assesses the impairment of long-lived assets whenever events or changes in business circumstances indicate that the carrying amounts of the asset or group of assets may not be fully recoverable. In the case of property and equipment and right-of-use assets for the Company's leases, the Company determines whether there has been an impairment by comparing the carrying value of the group of assets to the anticipated undiscounted net future cash flows associated with the group of assets. If such cash flows are less than the carrying value, the Company writes down the group of assets to its fair value, which may be measured as anticipated net cash flows associated with the group of assets, discounted at a rate that the Company believes a market participant would utilize to reflect the risks associated with the cash flows, such as credit risk.
Restructuring	Restructuring Employee severance costs are recorded based on whether the termination benefits are provided under an on-going benefit arrangement or under a one-time benefit arrangement. The Company accounts for on-going termination benefit arrangements, such as those arising from employment agreements, applicable regulations or past practices, in accordance with Accounting Standards Codification (“ASC”) Topic 712, Compensation-Nonretirement Postemployment Benefits (“ASC 712”). Under ASC 712, liabilities for post-employment benefits related to past services and that vest or are accumulated over time are recorded at the time the obligations are probable of being incurred and can be reasonably estimated. The Company accounts for one-time employment benefit arrangements in accordance with ASC Topic 420, Exit or Disposal Cost Obligations (“ASC 420”). One-time termination benefits are expensed at the date the entity notifies the employee, unless the employee must provide future service over a period extending past the minimum notification period, in which case the benefits are expensed ratably over the future service period. Other associated costs are recognized in the period in which the liability is incurred. See Note 12 for additional information on the severance expense that the Company recognized for employees terminated in connection with the reduction in force.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In December 2023, the Financial Accounting Standard Board ("FASB") issued Accounting Standards Update (“ASU”) No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures ("ASU 2023-09"). ASU 2023-09 is intended to enhance the transparency and decision usefulness of income tax disclosures. The amendments in ASU 2023-09 address investor requests for enhanced income tax information primarily through changes to the rate reconciliation and income taxes paid information. ASU 2023-09 will be effective for us in the annual period beginning January 1, 2025, though early adoption is permitted. The Company is currently evaluating the presentational effect that ASU 2023-09 will have on its financial statements and related disclosures. In November 2024, the FASB issued ASU No. 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses (“ASU 2024-03"). In January 2025, the FASB issued ASU 2025-0, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date, to clarify the effective date of ASU 2024-03. These amendments require public entities to disclose specified information about certain costs and expenses on an interim and annual basis and is effective for annual reporting periods beginning after December 15, 2026 and interim periods beginning after December 15, 2027, with early adoption permitted. The new standards are expected to be applied prospectively, but retrospective application is permitted. The Company is currently evaluating the impact on the financial statements and related disclosures. There were no other significant updates to the recently issued accounting standards other than as disclosed herewith. Although there are several other new accounting pronouncements issued or proposed by the FASB, the Company does not believe any of those accounting pronouncements have had or will have a material impact on its financial position or operating results.

Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Nkarta, Inc. 10-Q