This module uses the DevExpress PDF Document API to convert PDF files to PDF/A format. You can process the sample file or supply your own document. To do the latter, select Upload a File from the file selection drop-down menu.
Use the Convert to... dropdown button to select the compatibility level (PDF/A-1b, PDF/A-2b, or PDF/A-3b), convert the document, and download the result.
Sample document
Sample_Main.pdf
using DevExpress.Pdf;
Stream ConvertToCompatible(Stream documentStream, PdfCompatibility compatibilityLevel) {
using var converter = new PdfDocumentConverter(documentStream);
var outputStream = new MemoryStream();
converter.Convert(compatibilityLevel);
converter.SaveDocument(outputStream);
outputStream.Position = 0;
return outputStream;
}