How to convert JPG to PDF: your questions answered

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People usually arrive here with a pile of photos: pages of a signed form taken on a phone, receipts, a handwritten note, several shots of a damaged parcel. The recipient wants one file. These are the questions that come up, answered in the order you are likely to ask them.

How do I turn JPG files into one PDF?

1. Open JPG to PDF.
2. Add your images by choosing them or dragging them in. You can add up to 30.
3. Arrange them. The pages of the PDF follow the order of the list, so put the first page first.
4. Choose the page size (more on that below).
5. Convert, and keep the tab open until the download is ready.
6. Save convertmango-images.pdf, rename it to something meaningful, and open it to check.

The conversion runs in your browser, and the file contents are not uploaded to ConvertMango's conversion service.

Convert it now: JPG to PDF.

What are the limits?

Forty megapixels is far more than most phone photos, so the 50 MB total is the limit you are more likely to meet. If you hit it, make two PDFs, then join them with Merge PDF. The merge guide covers the order and size checks.

Which page size should I choose?

There are two options.

• Fit to image. Each page is fitted to its picture, so a landscape photo should give a landscape page and different images can give pages of different shapes.
• A4 portrait. Every page is the same size. Use this for anything that will be printed, signed, or stapled into a pile of paper, or when a portal expects ordinary document pages.

If you are unsure, choose A4 portrait for documents and Fit to image for photographs. Try both on two images before you commit a whole batch.

Is the PDF a document or a picture?

A picture, in a PDF wrapper. The Library of Congress describes PDF as a format for page-oriented documents that can hold text, still images and more, and it notes that a PDF built from scanned page images may not support text indexing. That is the situation here: your JPGs go in as images, so the words in them are pixels, not characters.

In practice this means you cannot search for a word, copy a paragraph, or have a screen reader read the page. The tool's own notes say the same: it makes an image-based PDF, not searchable or editable text, and getting usable text out of scanned pages requires OCR (text recognition). ConvertMango does not provide OCR, so if searchable text matters, produce the PDF from the original document instead of from photographs of it.

Does my image quality change?

Slightly, possibly. The tool normalises images to JPEG on a white background, so compression can change fine detail, as its own notes put it. MDN describes JPEG as lossy, meaning detail is discarded to save space. Do not assume the pixels in the PDF are identical to the file you started with.

Keep your original photos. The PDF is a delivery copy.

What about transparency?

A JPG cannot have a transparent background, since MDN notes JPEG does not support an alpha channel, so there is nothing to lose when converting a JPG. If your source is a PNG with see-through areas, those areas are flattened onto white. The PNG to PDF guide covers that case.

How can I make sure the pages come out the right way up?

Check every page of the finished PDF. If a page is sideways, rotate and save the photo in your photo app, then convert again.

How do I keep the PDF small enough to send?

• Photograph documents in good light but do not use the highest resolution setting if the camera offers choices. A page of text does not need 40 megapixels.
• Convert only the pages you need.
• If the PDF is still large, send two smaller PDFs rather than one.

Many email systems and upload forms have their own attachment limits that are not the same as ConvertMango's. Check the recipient's instructions before you send.

Can I add a PDF page to the middle later?

Yes, but you do it by joining PDFs. Make the extra page with JPG to PDF, then use Merge PDF to combine it with the existing PDF in the order you want. If you need to take pages out or reorder them, Extract PDF pages saves selected pages as a new PDF. Both tools have limits of their own (50 MB, and no password-protected files), so read the guide to extracting pages first.

Can I get the images back out?

Yes, as pictures of the pages. PDF to JPG renders each page as a JPG image. Note that it makes a fresh picture of the page; it does not recover the embedded original files, so the results may differ slightly from the photos you started with.

When should I not convert?

• The recipient accepts JPGs. Send the images; a PDF adds nothing.
• You need editable or searchable text. Start from the source document, or use OCR software.
• The PDF needs to be an official archive copy. Ask whoever sets the requirement what they accept.
• You have only one photo and want to enlarge it. A PDF will not add detail.

Is there a quick checklist?

1. Rotate and crop the photos first.
2. Name or number them so the order is obvious.
3. Choose A4 portrait for documents, Fit to image for photographs.
4. Convert, then open the PDF and look at every page.
5. Rename the file and keep the originals.

Frequently asked questions

Related tools

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Sources

Plain-text references. Facts that could not be checked against a primary source were left out.

1. Library of Congress, 'PDF (Portable Document Format) family', https://www.loc.gov/preservation/digital/formats/fdd/fdd000030.shtml
2. MDN Web Docs, 'Image file type and format guide', https://developer.mozilla.org/en-US/docs/Web/Media/Guides/Formats/Image_types