PDF or JPG for poster printing: which file format to send

What is the difference between a PDF and a JPG?

A PDF is a container. It can hold vector shapes, live text with embedded fonts, raster images and page boxes that define the trim and bleed. A JPG is a single grid of pixels. Everything in it, including any text, has been turned into pixels at one fixed resolution.

JPG also uses lossy compression. The Library of Congress describes typical JPEG settings as reducing file size by 10:1 to 20:1, with quality depending on how hard the image is compressed, and notes that the format is limited to 8 bits per channel. Each time a JPG is edited and saved again, it is compressed again. That is why a JPG should be the last step in a workflow, exported once from a master file, and never the working file itself.

When is PDF the better choice for a poster?

Choose PDF whenever the poster includes type, a logo, a QR code, thin lines or a solid background that runs to the edge. Vector text and shapes stay sharp at any size, so a headline on a 24 x 36 poster has clean edges no matter how closely someone looks. The PDF can also carry the full page size including bleed, so the printer knows where the cut belongs.

For professional print exchange there is a stricter family called PDF/X, published as ISO 15930. The Library of Congress summary explains that it requires all fonts and images to be embedded, trim and bleed boxes to be defined and color spaces to be specified through an output intent, so a file can be printed predictably without back and forth. Not every PDF meets that bar. The GPO publishing guidelines caution that PDF files created for web use may not output well in print because of resolution and color settings.

When is a JPG good enough for a poster?

A JPG can work well for a poster that is essentially one photograph, such as a wall print of a landscape or a portrait with no text. In that case the file is pixels either way, and a PDF wrapper adds nothing. What matters is enough resolution at the final size and a high quality export.

Export at the highest quality setting and at the full pixel dimensions, at least 150 pixels per inch at the printed size and ideally 300. The GPO guidelines also advise avoiding in camera compression where possible and using the highest quality option when compression is needed. If the poster has any lettering smaller than a headline, switch to PDF.

How do PDF and JPG compare for poster printing?

Does saving a poster as a PDF improve image quality?

No. A PDF preserves whatever you put into it. A low resolution photo or a screenshot saved as a PDF still prints at screenshot quality, and renaming a file from .jpg to .pdf changes nothing inside it. Export from the original design file so text stays as vector type.

Watch the export settings as well. Presets meant for small file sizes often downsample images and apply heavy compression, which can blur photographs that looked fine in the design. Choose a print or high quality preset and confirm that downsampling is off or set above your target resolution.

What about PNG and TIFF for posters?

PNG is lossless and handles sharp graphics well, but it is designed for screens and is usually RGB with no page size or bleed information. TIFF is a lossless raster format that many printers accept for photographs. Both are still raster images, so text inside them has the same limits as a JPG. The GPO guidelines list GIF, BMP and similar formats as unsuitable for most print production. When in doubt, follow the printer's list of accepted formats.

How do you check a poster file before you send it?

Open the exported file in a separate viewer, not the design program, and inspect it as the printer will see it.

• Confirm the page size equals the trim plus bleed.
• Zoom to 100 percent or more and check type, logos and QR codes.
• Check that fonts are embedded or converted as the printer requests.
• Confirm images meet at least 150 PPI at the final size.
• Look for heavy compression artifacts around edges and in skies.
• Keep the editable original and the full resolution images.
• Name the export clearly so the approved version is easy to identify.

Voqado's Studio print PDF embeds supported fonts and sets page boxes, but it is RGB and is not a PDF/X export, so ask for a proof when color matters. For the full routine, see the poster preflight checklist, the guide to preparing artwork for print and the notes on bleed and trim. The print resolution calculator can confirm pixel counts, and the guide to calculate poster resolution explains the math. When the file is ready, upload it to a custom poster order.