Results for the Year - A reconciliation of Genmab's effective tax (Details) - DKK (kr) kr in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Results for the Year
Net result before tax	kr 7,035	kr 3,983	kr 5,904
Tax at the Danish corporation tax rate of 22% for all periods	1,548	876	1,299
Adjustment to unrecognized deferred tax assets	(92)	137	67
Recognition of previously unrecognized tax losses and deductible temporary differences	(12)	119	(222)
Non-deductible expenses/non-taxable income and other permanent differences, net	73	(147)	(5)
All other	(4)	(10)	7
Total tax effect	(35)	99	(153)
Total tax expense (income)	1,513	975	1,146
Total tax for the period in shareholders' equity	kr (22)	kr (31)	kr (44)
Effective Tax Rate	21.50%	24.50%	19.40%
Applicable tax rate	22.00%	22.00%	22.00%

The increase (decrease) in equity resulting from tax on items recognized directly in equity.

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The amount of non-deductible expenses/non-taxable income and other permanent differences, net

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The amount of non-deductible expenses/non-taxable income and other permanent differences, net

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The amount of tax effect of adjustment to unrecognized deferred tax assets.

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The applicable income tax rate.

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The tax expense (income) divided by the accounting profit. [Refer: Accounting profit]

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The amount of current tax expense (income) and adjustments for the current tax of prior periods. [Refer: Current tax expense (income); Adjustments for current tax of prior periods]

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The aggregate amount included in the determination of profit (loss) for the period in respect of current tax and deferred tax. [Refer: Current tax expense (income); Deferred tax expense (income)]

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The amount that represents the difference between the tax expense (income) and the product of the accounting profit multiplied by the applicable tax rate(s) that the entity does not separately disclose in the same statement or note. [Refer: Accounting profit; Applicable tax rate]

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The profit (loss) before tax expense or income. [Refer: Profit (loss)]

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