JPG to PDF Converter Free Online Tool 2026

Last updated March 22, 2026

How JPG to PDF Conversion Works

Converting a JPG image to PDF embeds the raster image inside a PDF container. The PDF format (Portable Document Format) was designed by Adobe to present documents consistently across platforms. When you embed a JPG in a PDF, the image data is stored as a compressed stream inside the PDF file structure, wrapped with metadata like page size, orientation, and DPI.

PDF Page Size and Image Scaling

Using jsPDF in the Browser

import { jsPDF } from 'jspdf';

async function jpgToPdf(imageFile) {
  const url = URL.createObjectURL(imageFile);
  const img = new Image();
  img.src = url;
  await new Promise(r => img.onload = r);

  const pdf = new jsPDF({
    orientation: img.width > img.height ? 'landscape' : 'portrait',
    unit: 'px',
    format: [img.width, img.height]
  });

  pdf.addImage(img, 'JPEG', 0, 0, img.width, img.height);
  pdf.save('output.pdf');
  URL.revokeObjectURL(url);
}

Quality Considerations

JPG uses lossy compression — each save cycle degrades quality slightly. For best results, use the original high-resolution JPG rather than a screenshot or re-saved copy. If you need text to remain selectable in the PDF, use OCR-based conversion instead of simple image embedding. For scanned documents, 300 DPI is the standard for readable text.