v3.25.2
Basis of presentation (Tables)
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]    
Schedule of subsidiaries in consolidation
                   
    Country of   Ownership Interest   Statements of Operations
Company Name   Incorporation   Direct   Indirect   2025   2024
Advent Technologies, Inc.   USA   100%   -   01/01 – 6/30   01/01 – 6/30
Advent Technologies S.A.   Greece   -   100%   01/01 – 6/30   01/01 – 6/30
Advent Technologies LLC   USA   -   100%   01/01 – 6/30   01/01 – 6/30
Advent Technologies GmbH   Germany   100%   -   01/01 – 6/30   01/01 – 6/30
                                 
    Country of     Ownership Interest     Statements of Operations  
Company Name   Incorporation     Direct     Indirect     2024     2023  
Advent Technologies, Inc.   USA       100 %     -     01/01 – 12/31     01/01 – 12/31  
Advent Technologies S.A.   Greece       -       100 %   01/01 – 12/31     01/01 – 12/31  
Advent Technologies LLC   USA       -       100 %   01/01 – 12/31     01/01 – 12/31  
Advent Technologies GmbH   Germany       100 %     -     01/01 – 12/31     01/01 – 12/31