How to Convert JPG Images to PDF

14 January 2025 · 4 minute read · By OmniPDF Product Team

JPG is the universal photo format. PDF is the universal document format. When you need to send a photo as a document — a scanned ID, a photographed receipt, screenshots of a chat, photos of a whiteboard — converting to PDF makes it look professional and prevents accidental edits.

JPG to PDF is also the first step in most document-digitisation workflows. You photograph pages with your phone, convert the photos to PDF, then run OCR to make the text searchable. This guide shows how to do the first step well.

The basic conversion

Open the JPG to PDF tool.
Add one or more JPG or JPEG images. Each image becomes one page.
Reorder the images if needed using the up and down arrows.
Choose a page size: Auto (match each image's dimensions), A4, Letter or Legal.
Choose orientation: Auto (portrait or landscape based on the image), Portrait or Landscape.
Set an optional margin in points (0 for full-bleed).
Click Convert to PDF.

Page size: Auto vs A4

This is the choice that most affects the result, and it depends on the use case.

Auto

Each PDF page matches the dimensions of the corresponding image. If your image is 1200×1600 pixels, the page is 1200×1600 points (one point equals one pixel at 72 DPI). This is the right choice for:

Photos that should not have white borders.
Scans where you want the PDF to match the original paper size exactly.
Image-based flyers or graphics.

A4 / Letter / Legal

Every page is A4 (595×842 points), Letter (612×792 points) or Legal (612×1008 points). The image is scaled to fit inside the page with the specified margin. Whitespace may appear on the sides if the image aspect ratio doesn't match the page. This is the right choice for:

Documents that should print on standard paper.
Scans of documents that should be A4-sized PDFs.
Photos that will be shared as normal-looking documents.

Quality preservation

OmniPDF's JPG to PDF tool embeds the original JPG directly into the PDF. No re-encoding happens, so image quality is preserved exactly. A 3 MB photo becomes a 3 MB page in the PDF (plus a small overhead for the PDF structure).

This is different from the compression tools, which do re-encode. If you want the PDF to be smaller, use Compress PDF after creating it.

Multiple images: how they combine

If you add 10 images, you get a 10-page PDF, one image per page, in the order they appear in the file list. Use the ↑ and ↓ arrows on each file card to change the order before converting. Clicking the × on a card removes that image from the list.

EXIF orientation

Most phone photos are stored with an EXIF "orientation" tag: the pixels are in landscape, but the tag says "rotate 90° for display." The JPEG loader in browsers reads that tag automatically, so photos appear upright. OmniPDF respects the auto-rotated dimensions when building the PDF page.

Some sources — such as certain Android camera apps and older tools — strip the EXIF tag, in which case the photo appears sideways. If this happens, rotate the image first using the Rotate PDF tool after conversion, or fix the photo in a photo editor before converting.

Combining photos with a signature

A common workflow is: photograph a signed contract, then combine the photo with a typed cover letter into a single PDF. OmniPDF supports mixed image types in the same PDF:

Convert the cover letter (Word or TXT) to PDF using Word to PDF.
Convert the contract photo to PDF with JPG to PDF.
Merge both PDFs using Merge PDF.

Making the resulting PDF searchable

A JPG in a PDF is just an image. The text inside the image is not searchable or copyable. If you need searchable text — for archival, indexing, or future editing — add an OCR step:

Convert the JPGs to PDF with the tool above.
Run OCR PDF on the result. This recognises the text and produces a searchable version.
Or use Make PDF Searchable to add an invisible text layer over the existing images.

Compressing the result

JPG to PDF produces a PDF that is essentially the sum of the source images plus a small overhead. If your phone photos are 3–5 MB each, ten of them produce a 30–50 MB PDF. To reduce that:

Compress the source images in a photo editor first (crop, resize to 2000px longest edge, save at quality 80).
Or convert to PDF and then use Compress PDF at the Balanced level.
Or use Reduce PDF Image Size for finer control.

Privacy

All processing happens in your browser. Your photos never leave your device. This is safe for sensitive documents like ID scans, medical records and personal photographs.

Summary

JPG to PDF is a simple conversion with one important decision: page size (Auto for image-native dimensions, A4/Letter for print-style documents). Quality is preserved because no re-encoding happens. Combine with OCR if you need searchable text, and compress afterwards if the resulting file is too large.