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My product catalog PDF made from photos is huge. How do I make it lighter?

Compress the photos before you turn them into a PDF. The images to PDF tool places JPEG files into the document byte for byte, so the catalog ends up close to the total size of its photos. Compress them all as JPEG at around quality 75, then build the catalog from the compressed files. Choose JPEG specifically, because WebP files get re-encoded on their way into a PDF.

Published · 3 min read

Why the catalog comes out huge

Put 16 phone photos into a PDF and the file carries all sixteen at full size. There is nothing magic in the PDF format that shrinks them. That is why the catalog fails to send over WhatsApp or email, or why a customer hesitates to download it on mobile data. The fix is not in the PDF itself; it is in the photos before they go in.

Why JPEG and not WebP here

  • The Images to PDF tool embeds JPEG and PNG files byte for byte with no re-encoding, so a compressed photo keeps its size.
  • PDF cannot hold WebP, so that tool converts WebP images to JPEG at quality 92, or to PNG if they have transparency. That is a second round of compression, and often a bigger file than the one you compressed.
  • Photographic PNGs go in as they are, too, and they are very heavy. Convert them to JPEG in the compressor first.
  • Images from the compressor carry no EXIF orientation flag, so the PDF tool has no reason to rotate and re-encode them.

How much smaller the catalog gets

Worked example

A 1600×1200 product photo of 689.5 KB became 201.5 KB as JPEG at quality 75 in Chrome.

If the catalog had 16 similar photos, their total would drop from about 10.8 MB to about 3.15 MB, 70.8% smaller.

Reduce each photo to 1200×900 before compressing at quality 75, and each becomes 100.4 KB, about 1.57 MB for all sixteen.

The final PDF comes out close to the total of the photos, plus a little for the document structure.

Step by step

  1. Add the catalog photos to the Image compressor, up to 30 at a time.
  2. Choose JPEG at quality 75 and check the Total line, which is a good preview of the catalog's size.
  3. Download the ZIP and extract it into a folder.
  4. Open the images to PDF tool, add the compressed photos, arrange them, and create the file.
  5. Open the PDF on your phone and make sure the photos still look clear when zoomed.

Is the catalog for print or for screens?

Everything above is for a catalog that gets sent and browsed on phones. If it is going to a printer, the decision is completely different: printers need higher resolution photos and usually set their own requirements, so ask them and do not compress hard. You can make two versions: a light one for WhatsApp and email, and a full one for print built from the originals.

Common questions

Should I compress the PDF after creating it instead?

This compressor works on images only. Compressing the photos before building the file is how you control the quality precisely.

How many photos can the catalog hold?

The compressor handles up to 30 images at a time. For a bigger catalog, compress in rounds and then add them all.

Are my product photos uploaded during any of this?

No, both compressing and building the PDF happen in your browser.