Hello,
PDF24 has no paper size setting of its own for scanning. When you click From scanner in PDF24 OCR and choose your scanner under Select source, PDF24 opens the window of your scanner driver. The paper size (or scan area), resolution and color are set there, and the scanned page has the size that the scanner delivers.
If that window does not offer A4 or does not keep the setting:
- In the Select source window your scanner is often listed more than once, in the groups x64, x86 and x86 MS. Each of them opens a different driver window. Please try the scanner from another group.
- If none of them lets you choose A4, please tell us the model of your scanner and which group you used.
For PDF files that already exist, text recognition also works online: https://tools.pdf24.org/en/ocr-pdf