You’ve briefed your designer. The artwork looks great on screen. Your brand colours are vibrant, the logo is sharp, and the layout is exactly what you imagined. You send the file to your packaging supplier — and the print comes back wrong. The colours are dull. The logo is pixelated at the edges. The design is cut off on one side.
This is the most common and most expensive mistake in custom packaging: artwork that looks correct on screen but isn’t print-ready. The gap between a beautiful design file and a correctly printed box is entirely technical — and entirely preventable if you know what to check before you submit.
This guide covers every file specification your printer needs: dieline setup, bleed and safe zones, colour modes, resolution requirements, and the pre-submission checklist that prevents costly reprints. For the upstream step of briefing your designer correctly in the first place, see our guide on How to Brief a Designer for Custom Food Packaging.
Step 1: Start with the Correct Dieline
A dieline is the flat, unfolded template of your packaging item — showing the exact printable surface, fold lines, glue tabs, bleed zones, and safe zones. Every piece of artwork must be created on the supplier’s dieline, not on a generic template.
Why this matters: packaging dimensions vary by supplier. A burger box from Supplier A may have slightly different dimensions than the same-sized box from Supplier B. If your designer creates artwork on a generic template and your supplier uses different dimensions, the artwork won’t align with the fold lines. You’ll end up with text that disappears into a fold or a logo that’s cut off at the edge.
The correct workflow:
- Confirm your packaging supplier and the specific SKUs you’re ordering
- Request the dieline files from your supplier (provided as .AI or .PDF)
- Send the dielines to your designer before any creative work begins
- Designer creates all artwork within the dieline, on a separate locked layer
- Submit artwork back to supplier with the dieline layer visible for alignment verification
At Toppaq, dieline files are provided for all custom packaging SKUs as part of the ordering process. Never start artwork without the supplier’s dieline in hand.
Step 2: Understand Bleed, Safe Zone, and Cut Line
These three zones are the foundation of any print-ready file. Getting them wrong is the most common cause of packaging artwork rejection.
The Cut Line
The cut line (also called the trim line) is the exact edge of the finished packaging item after it has been cut. This is where the physical box or bag ends. Any artwork that needs to extend to the very edge of the packaging must extend beyond the cut line into the bleed zone.
The Bleed Zone
The bleed zone is an extension of your artwork beyond the cut line — typically 3 mm on all sides for food packaging. It exists because cutting machines have a small tolerance: the cut may land 1–2 mm inside or outside the cut line. If your background colour or image stops exactly at the cut line and the cut lands 1 mm inside, you’ll see a thin white strip at the edge of the finished box.
The bleed zone ensures that even if the cut is slightly off, the artwork still extends to the edge with no white gaps. Standard bleed for food packaging: 3 mm on all sides. Some suppliers require 5 mm — always confirm with your specific supplier.
The Safe Zone
The safe zone is the area inside the cut line where all critical content — logos, text, important design elements — must be kept. Typically 3–5 mm inside the cut line. Any text or logo placed outside the safe zone risks being cut off if the cut lands slightly inside the cut line.
The rule: Background colours and patterns extend into the bleed zone. Logos, text, and critical design elements stay inside the safe zone. Nothing important goes between the safe zone and the cut line.
| Zone | What Goes Here | Standard Dimension |
|---|---|---|
| Bleed zone | Background colours, patterns, images that extend to edge | 3–5 mm beyond cut line |
| Cut line | The physical edge of the finished packaging | Defined by dieline |
| Safe zone | Logos, text, critical design elements | 3–5 mm inside cut line |
Step 3: Colour Mode — The Most Misunderstood Specification
This is where the most expensive mistakes happen. Colour mode determines how colours are defined in your file — and the wrong colour mode produces colours that look completely different when printed compared to what you see on screen.
RGB: Screen Colours (Wrong for Print)
RGB (Red, Green, Blue) is the colour mode used by screens — monitors, phones, tablets. RGB colours are created by mixing light, which allows for a very wide range of vivid, saturated colours. When you design in RGB and view the file on screen, the colours look vibrant and accurate.
When you send an RGB file to a printer, the printer must convert the RGB values to printable ink colours. This conversion is imprecise and unpredictable — the printer’s software makes its best guess, and the result is often significantly different from what you saw on screen. Bright blues become dull. Vibrant oranges shift toward brown. Neon greens become muddy.
Never submit packaging artwork in RGB.
CMYK: Process Colour Printing
CMYK (Cyan, Magenta, Yellow, Key/Black) is the standard colour mode for commercial printing. It defines colours as percentages of four ink channels. Most digital and offset printing processes use CMYK.
For food packaging printed using digital or offset processes (typically used for shorter runs or full-colour photographic designs), CMYK is the correct colour mode. Convert your file from RGB to CMYK before submission and check the colours carefully after conversion — some RGB colours don’t have a CMYK equivalent and will shift.
Pantone (PMS): Spot Colour Printing
Pantone Matching System (PMS) colours are standardised spot colours — each Pantone colour is a specific pre-mixed ink with a unique reference number. When you specify Pantone 485 C (a specific red), every printer in the world using that Pantone ink will produce the exact same red, regardless of their equipment.
For food packaging printed using flexographic printing — the most common process for kraft boxes, paper bags, and cups at MOQs of 1,000–5,000 units — Pantone spot colours are the correct specification. Flexographic printing uses one physical ink plate per colour, and each plate is inked with a specific Pantone colour. This is why flexographic printing is limited to a small number of colours (typically 1–3) but produces extremely consistent, vibrant results on kraft paper.
For the full explanation of flexographic printing and its design constraints, see our guide on How to Brief a Designer for Custom Food Packaging.
Which Colour Mode to Use
| Print Process | Correct Colour Mode | Typical Use Case |
|---|---|---|
| Flexographic printing | Pantone (PMS) spot colours | Kraft boxes, paper bags, cups at 1,000–5,000 MOQ |
| Digital printing | CMYK | Short runs, full-colour photographic designs |
| Offset printing | CMYK or Pantone | High-volume, premium packaging |
| Screen printing | Pantone (PMS) spot colours | Fabric bags, specialty items |
Step 4: File Format and Resolution
Vector vs. Raster: The Most Critical Distinction
All logos, icons, and text in your packaging artwork must be in vector format. Vector graphics are defined mathematically — they can be scaled to any size without any loss of quality. A vector logo looks identical whether it’s 1 cm or 1 metre wide.
Raster graphics (JPG, PNG, photographs) are defined by pixels. When you scale a raster image up, the pixels become visible — the image looks blurry or pixelated. A logo saved as a JPG and placed in a packaging file will look sharp on screen at the design size, but when the printer outputs the file at full scale, the pixelation becomes visible.
Vector formats: .AI (Adobe Illustrator), .EPS, .SVG, .PDF (vector-based)
Raster formats: .JPG, .PNG, .TIFF, .PSD (pixel-based)
If your logo only exists as a JPG or PNG, your designer must redraw it in vector format before any packaging artwork begins. This is a one-time cost that pays for itself across every print run.
Resolution for Raster Elements
If your design includes photographic elements (product photography, textures, background images), these must be at a minimum resolution of 300 DPI (dots per inch) at the final print size. A photograph that is 300 DPI at 10 cm wide becomes 150 DPI if you scale it to 20 cm wide — below the minimum threshold for sharp print output.
The rule: always work with the highest resolution source image available, and check the DPI at the final print size before submission.
Accepted File Formats for Submission
- .AI (Adobe Illustrator): The preferred format for most packaging suppliers. All fonts must be outlined (converted to vector paths) so the supplier doesn’t need your fonts installed.
- .PDF (print-ready): Widely accepted. Must be exported with bleed marks, crop marks, and all fonts embedded or outlined. Use PDF/X-1a or PDF/X-4 export presets.
- .EPS: Accepted by most suppliers. Older format but still widely used for vector artwork.
- Not accepted: .JPG, .PNG, .DOCX, .PPTX, .PSD (unless specifically requested for raster-only elements)
Step 5: Font Handling
Fonts are one of the most common causes of artwork rejection. If your designer submits a file with live (unoutlined) fonts and the supplier doesn’t have those fonts installed, the text will either be substituted with a default font or the file will fail to open correctly.
Always outline all fonts before submission. In Adobe Illustrator: Select All → Type → Create Outlines. This converts all text to vector paths, eliminating any font dependency. Once outlined, text cannot be edited — keep a working copy of the file with live fonts for future edits.
Step 6: Overprint and Knockout Settings
Overprint and knockout settings determine how overlapping colours interact in the print output. Incorrect settings can cause colours to appear muddy or disappear entirely.
- Knockout (default): The top colour blocks out the colour beneath it. A white logo on a coloured background knocks out the background colour, leaving the paper/substrate showing through the white area.
- Overprint: The top colour prints on top of the colour beneath it, mixing the two inks. Overprint is used intentionally for specific effects but causes problems when applied accidentally — particularly to white elements, which become invisible when set to overprint (since white ink overprinting on a coloured background produces no visible result).
Check your overprint settings in Illustrator via View → Overprint Preview before submission. White elements should never be set to overprint.
The Print-Ready File Submission Checklist
Before sending any artwork file to your packaging supplier, verify every item on this checklist:
- ☐ Artwork created on supplier’s dieline (not a generic template)
- ☐ Bleed zone: 3–5 mm beyond cut line on all sides
- ☐ Safe zone: all logos and text 3–5 mm inside cut line
- ☐ Colour mode: Pantone PMS (flexo) or CMYK (digital/offset) — no RGB
- ☐ All logos and icons in vector format (.AI or .EPS source)
- ☐ All raster images at minimum 300 DPI at final print size
- ☐ All fonts outlined (converted to vector paths)
- ☐ File format: .AI or print-ready .PDF with bleed and crop marks
- ☐ Overprint preview checked — no unintentional overprint on white elements
- ☐ Dieline layer visible and unlocked for supplier alignment check
- ☐ FSSAI license number included as mandatory text (if applicable)
For the full guide on what mandatory compliance text must appear on food packaging, see our guide on How to Brief a Designer for Custom Food Packaging.
What Happens After You Submit: The Print Proof Process
Even with a perfectly prepared file, always request a print proof before approving the full production run. A print proof is a single unit printed on the actual substrate (kraft paper, PLA, etc.) using the actual print process. It shows you exactly how the colours, resolution, and layout will look on the finished packaging.
Print proofs typically cost ₹500–2,000 depending on the packaging type and supplier. This is the most important ₹500–2,000 you’ll spend in the entire packaging process — it’s the only way to catch colour shifts, resolution issues, or layout problems before they’re replicated across 1,000+ units.
Approve the print proof in writing before authorising the production run. Keep a physical copy of the approved proof for reference against future reorders.
GST ITC on Design and Print Costs
Design fees paid to GST-registered designers or studios, and printing costs from GST-registered packaging suppliers, are both eligible for Input Tax Credit if your business is GST-registered under an eligible framework. For the complete ITC claim process, see How to Claim 18% GST Input Tax Credit on Restaurant Packaging.
Ready to Print? Source with Toppaq
Once your artwork is print-ready and approved, Toppaq handles the rest — custom printing on kraft boxes, paper bags, cups, and containers across India, starting at 1,000 pieces with GST-compliant B2B invoicing and pan-India doorstep delivery. Dieline files provided for all SKUs. For the complete range, see our Complete Packaging Checklist for New Cloud Kitchens.