How to Create a ZIP Folder Archive

Published January 19, 2023 · Updated March 16, 2026

Do you have a significant number of artwork files to upload for your order?

You can easily turn multiple files into one file by compressing them into a .ZIP folder archive. Depending on how many components your order includes and how your artwork files were prepared, you may have multiple files to upload. While our system does allow you to upload up to five files at once, if you find yourself needing to make multiple uploads for each round of proofing, it may be more efficient to create .ZIP folder archives and then upload the resulting .ZIP file(s). Note that our upload system can only accept files that are smaller than 2GB, so you may need to break up your files into multiple .ZIP folder archives.

Is your design program crashing everytime you try to export your artwork?

This is more than likely because you are trying to export out a file larger than 2GB. Remember, creating your artwork at a resolution higher than 300DPI does not improve the overall print quality. Rather, in many cases it can actually cause crashes in both our and our vendors’ prepress programs. If you find your artwork file is over 2GB or your design program keeps crashing when trying to export out a multiple-page PDF we recommend doing one of the following:

Save each page/spread as INDIVIDUAL PDF files.
Try exporting out the pages/spreads in BATCHES instead of the whole book
at once.

Whichever option you choose, you should now have multiple files that you are ready to upload. If you have less than five files that total less than 2GB in file size, you can go ahead and upload them as-is. If you have more than five files or your total file size is over 2GB, we recommend the following instructions to compress multiple files into one .ZIP folder archive (note that you can further organize your files into subfolders before compression if you’d like):

MAC:

Select the file(s) and/or folder(s) you want to compress. Right-click on your selection and click “Compress”:

PC:

Select the file(s) and/or folder(s) you want to compress. Right-click on your selection and click “Send to”, then click “Compressed (zipped) folder”.

This will compress your selection and allow you to upload the artwork.

Artwork File Best Practices

Before you zip and upload, make sure your files are print-ready. Following these guidelines will help avoid prepress delays and ensure your project prints exactly as intended.

File Format

Format	Best For	Notes
PDF/X-1a	All print projects	The gold standard. Embeds fonts, flattens transparency, enforces CMYK. Defined by ISO 15930-4.
Press-quality PDF	All print projects	Adobe’s preset that closely mirrors PDF/X-1a requirements. Widely accepted.
TIFF (.tif)	Raster artwork, photos	Lossless compression. Large file sizes but zero quality loss.
Adobe Illustrator (.ai)	Vector artwork, logos, line art	Best for resolution-independent graphics. Convert all fonts to outlines before saving.
PSD (.psd)	Complex layered artwork	Flatten layers and convert to CMYK before submission to avoid unexpected results.

Avoid JPG for final print files — JPG uses lossy compression that introduces artifacts visible in print, especially in flat color areas and gradients. If you must use JPG, save at maximum quality (12 in Photoshop) with no downsampling.

Resolution

300 DPI — The industry standard for full-color print work. This resolution produces approximately 118 pixels per centimeter, which is beyond what the human eye can distinguish at normal reading distance (per the ISO 12647 print production standards).
400+ DPI — Recommended for black-and-white line art (comics, pen-and-ink illustrations) where jagged edges are more visible than in photographs.
Above 300 DPI for photos — Unnecessary. Higher resolution increases file size dramatically without any visible improvement in print quality. A 300 DPI image at 8.5″ x 11″ is approximately 30 MB as a TIFF; at 600 DPI, the same image would be 120 MB — four times larger with no perceptible difference.

Color Mode

All artwork should be submitted in CMYK (Cyan, Magenta, Yellow, Key/Black) color mode — not RGB. RGB is the color model for screens; CMYK is the color model for print. If you submit RGB files, they will be converted to CMYK during prepress, and some colors will shift — particularly bright blues, greens, and oranges that fall outside the CMYK gamut.

To convert in Adobe Photoshop: Image → Mode → CMYK Color. In InDesign or Illustrator, ensure your document color mode is set to CMYK from the start.

Bleed and Safe Area

Bleed: Extend all artwork that touches the page edge by 0.125″ (3 mm) beyond the trim line. This extra margin ensures no white edges appear if the cut is slightly off.
Safe area: Keep all critical content (text, logos, important image elements) at least 0.125″ (3 mm) inside the trim line — 0.25″ (6 mm) for covers and near the spine.

Organizing Your Files

Clear file organization speeds up prepress and reduces the chance of errors. We recommend:

Name files sequentially: interior_page_001.pdf, interior_page_002.pdf, etc. Avoid spaces and special characters in filenames.
Separate covers from interiors: Put cover files in a /covers/ subfolder and interior pages in an /interiors/ subfolder within your ZIP.
Include a README: If your project has special instructions (specific Pantone colors, non-standard page order, mixed paper stocks), include a plain text README.txt file in your ZIP.
One PDF per component: For game projects with multiple components (cards, board, rules, box), create a separate PDF for each component and label them clearly: playing_cards_front.pdf, game_board.pdf, rules_booklet.pdf, box_top.pdf, box_bottom.pdf.

File Size Troubleshooting

If your exported PDF is over 2GB, here are the most common causes and fixes:

Issue	Fix
Resolution above 300 DPI	Downsample images to 300 DPI in your design program before export. In InDesign: File → Export → Compression → Bicubic Downsample to 300 ppi.
Embedded vs. linked images	In Illustrator and InDesign, linked images keep file sizes smaller during editing. When exporting to PDF, images are embedded automatically — but starting with optimized source images matters.
Unflattened transparency	Complex transparency effects (drop shadows, opacity blends, feathered edges) can balloon PDF size. Use the PDF/X-1a preset, which flattens transparency automatically.
Unused hidden layers	Delete hidden layers before export. Some design programs include hidden layer data in the PDF even when not visible.

Common Prepress Errors

These are the issues our prepress team sees most frequently — avoiding them will save you a round of revisions:

RGB images in a CMYK document — Even if your document is set to CMYK, individual placed images may still be RGB. In InDesign, use Preflight (Window → Output → Preflight) to catch these.
Missing fonts — If fonts aren’t embedded or converted to outlines, they may substitute on our systems. Always embed fonts or convert text to outlines/paths before export.
Low-resolution images — Images pulled from the web are typically 72 DPI. They may look fine on screen but will print blurry. The PDF/X-1a standard doesn’t enforce minimum resolution, so this is something you need to check yourself.
Insufficient bleed — Artwork that stops exactly at the trim line will show white edges when cut. Always extend to the bleed line.
Rich black on text — Body text should be 100% K (black) only. Using a four-color “rich black” (e.g., C60 M40 Y40 K100) on small text causes registration issues where the color plates don’t align perfectly, creating a blurry, halo-like effect.