JPG, PNG, WEBP or HEIC: which image format to use and how it affects your PDF

Not all images are the same. The format a photo is saved in determines how big it is, whether it supports transparency and how much quality it keeps. Understanding the differences helps you choose well and get sharper, lighter PDFs.

JPG (or JPEG): the standard for photos

It's the most widely used format in cameras and phones. It uses "lossy" compression: it discards details the eye barely notices so the file stays small. It's perfect for photographs, but every time it's saved again it loses a bit of quality, and it doesn't support transparency. When converting to PDF, OrdenaPDF embeds it as is, without recompressing it.

PNG: sharpness for screenshots and graphics

PNG uses "lossless" compression: the image is kept exactly as it is. That makes it ideal for screenshots, diagrams, logos or any image with text and sharp edges. It supports transparency. The downside is that for photographs it's much larger than a JPG. In the PDF it's also embedded without loss.

WEBP and AVIF: the web's modern formats

Many websites serve images as WEBP or AVIF because they're much smaller than JPG at similar quality. If you save an image from your browser, it will probably end up in one of these formats. PDF doesn't support them directly, so they're converted to high-quality JPG (transparency is placed over a white background) when the document is created.

HEIC: iPhone photos

For years, iPhones have saved photos as HEIC, which takes about half the space of an equivalent JPG. The drawback is compatibility: many programs and browsers outside Apple's ecosystem can't open it. Safari can convert them; in other browsers it's easiest to set the camera to "Most Compatible" or export the photos as JPG.

GIF and BMP: older formats

GIF only supports 256 colors and today is used almost exclusively for short animations; when converted to PDF only the first frame is kept. BMP stores the image uncompressed, so files are huge. Both are converted to lossless PNG when the PDF is created.

Quick table: which format to choose

• Photo of a person, a landscape or a photographed document: JPG.
• Screenshot, chart, diagram or logo: PNG.
• Image downloaded from a website: usually WEBP; it works as is for the PDF.
• iPhone photos you'll share with other people: JPG is safer ("Most Compatible").
• Documents you'll print: any of the above, with good resolution (at least 1500 pixels on the long side for a letter-size page).