v3.25.4

Loss Per Share (Tables) | 12 Months Ended
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Sep. 30, 2025
Loss Per Share [Abstract] |
Schedule of Basic and Diluted Loss Per Share | Basic loss per share and diluted loss per share have been calculated in accordance with ASC 260 for the year ended September 30, 2023, 2024 and 2025 as follows:
|  |  |  |  |  |  |  |  |  |  | (Successor) |  |  | (Predecessor) |
|  | For the year ended September 30, 2025 |  |  | For the year ended September 30, 2024 |  |  | From October 12, 2022 to September 30, 2023 |  |  | From October 1, 2022 to October 11, 2022 |
|  | HK$ |  |  | US$ |  |  | HK$ |  |  | HK$ |  |  | HK$ |
Numerator: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss attributable to ordinary shareholders of Alpha Technology Group Limited |  |  | (70,409,731 | ) |  |  | (9,049,044 | ) |  |  | (5,487,765 | ) |  |  | (6,830,973 | ) |  |  | (156,387 | )
Denominator: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average number of ordinary shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
— Basic |  |  | 16,462,500 |  |  |  | 16,462,500 |  |  |  | 15,262,500 |  |  |  | 13,250,000 |  |  |  | 20,000 |
— Diluted |  |  | 16,432,830 |  |  |  | 16,432,830 |  |  |  | 14,933,987 |  |  |  | 1,169,808 |  |  |  | — |
Net loss per share attributable to ordinary shareholders |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
— Basic |  |  | (4 | ) |  |  | * |  |  |  | — |  |  |  | (1 | ) |  |  | (8 | )
— Diluted |  |  | (4 | ) |  |  | * |  |  |  | — |  |  |  | (6 | ) |  |  | — |
* | The balance represents an amount less than US$1.

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- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482662/260-10-50-1 + Details
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