Significant Accounting Policies (Policies)	3 Months Ended
Significant Accounting Policies (Policies)	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Accounting, Policy [Policy Text Block]	Basis of Presentation The accompanying unaudited interim condensed consolidated financial statements include the accounts of BIO-key International, Inc. and its wholly-owned subsidiary (collectively, the “Company” or “BIO-key”) and are stated in conformity with accounting principles generally accepted in the United States of America, pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). The operating results for interim periods are not necessarily indicative of results that may be expected for any other interim period or for the full year. Pursuant to such rules and regulations, certain financial information and footnote disclosures normally included in the financial statements have been condensed or omitted. Significant intercompany accounts and transactions have been eliminated in consolidation. In the opinion of management, the accompanying unaudited interim consolidated financial statements contain all necessary adjustments, consisting only of those of a recurring nature, and disclosures to present fairly the Company’s financial position and the results of its operations and cash flows for the periods presented. The balance sheet at December 31, 2019 was derived from the audited financial statements, but does not include all of the disclosures required by accounting principles generally accepted in the United States of America. These unaudited interim condensed consolidated financial statements should be read in conjunction with the financial statements and the related notes thereto included in the Company’s Annual Report on Form 10 -K for the fiscal year ended December 31, 2019, filed with the SEC on May 14, 2020.
New Accounting Pronouncements, Policy [Policy Text Block]	Recently Issued Accounting Pronouncements In August 2018, the FASB issued ASU No. 2018 - 15, Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract (“ASU 2018 - 15” ). ASU 2018 - 15 aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The update to the standard is effective for interim and annual periods beginning after December 15, 2019, with early adoption permitted. Entities can choose to adopt ASU 2018 - 15 prospectively or retrospectively. The Company has assessed that ASU 2018 - 15 currently does not have a material impact on its consolidated financial statements. In June 2016, the FASB issued ASU 2016 - 13, Financial Instruments-Credit Losses (Topic 326 ), referred to herein as ASU 2016 - 13, which significantly changes how entities will account for credit losses for most financial assets and certain other instruments that are not measured at fair value through net income. ASU 2016 - 13 replaces the existing incurred loss model with an expected credit loss model that requires entities to estimate an expected lifetime credit loss on most financial assets and certain other instruments. Under ASU 2016 - 13 credit impairment is recognized as an allowance for credit losses, rather than as a direct write-down of the amortized cost basis of a financial asset. The impairment allowance is a valuation account deducted from the amortized cost basis of financial assets to present the net amount expected to be collected on the financial asset. Once the new pronouncement is adopted by the Company, the allowance for credit losses must be adjusted for management’s current estimate at each reporting date. The new guidance provides no threshold for recognition of impairment allowance. Therefore, entities must also measure expected credit losses on assets that have a low risk of loss. For instance, trade receivables that are either current or not yet due may not require an allowance reserve under currently generally accepted accounting principles, but under the new standard, the Company will have to estimate an allowance for expected credit losses on trade receivables under ASU 2016 - 13. ASU 2016 - 13 is effective for annual periods, including interim periods within those annual periods, beginning after December 15, 2022 for smaller reporting companies. Early adoption is permitted. The Company is currently assessing the impact ASU 2016 - 13 will have on its condensed consolidated financial statements. Management does not believe that any other recently issued, but not yet effective, accounting standard if currently adopted would have a material effect on the accompanying consolidated financial statements.
Reclassification, Comparability Adjustment [Policy Text Block]	Reclassifications Certain balance sheet accounts have been reclassified to conform to the 2020 presentation.