Understanding CMYK and Colour Accuracy in Printing

Why Your Colours Look Wrong in Print (and How to Fix It)

You spent hours getting your label design just right. On screen, it looked sharp and vibrant. But when the printed version arrived, the colours were off - duller, muddier, or just not what you expected.

It’s one of the most common frustrations in label printing. And it usually comes down to one simple thing: the colour mode.

This guide breaks down why screen colours don’t always match printed ones, what CMYK actually means, and how to make sure your next label comes out looking the way you intended - whether you're working with a designer or trying to design stickers yourself.

Your screen uses RGB (red, green, blue) light to create colour. Printing uses CMYK (cyan, magenta, yellow and black) ink. They're two different systems that produce colour in different ways.

So when you design in RGB and send it to print, the colours get converted to CMYK. And in that conversion, some colours shift - especially vibrant ones like neon greens or deep blues. What looked bold on screen might end up muted on paper.

The key to fixing this? Start your design in CMYK from the beginning.

RGB (left) vs. CMYK (right)

SOURCE: https://fairwayprinting.com/blog/2016/3/2/rgb-vs-cmyk

CMYK is the industry standard for print. Every printed colour is made by blending these four inks in different percentages.

When you design in RGB, you're using colours that can’t always be replicated in ink. That’s why the printer has to guess the closest match - and why things sometimes look “off”.

If you care about colour accuracy - and for custom label printing, most brands do - designing in CMYK gives you far more control. It keeps your labels consistent with your branding, even across different batches or materials.

1. Designing in RGB
   Most software starts in RGB by default. Always check and switch to CMYK if you’re designing for print.
   
   

2. Wrong File Format
   PNGs and JPEGs are for screens. For print, always export a high-resolution PDF with crop marks and bleed.
   
   

3. Low Resolution
   Anything under 300dpi will look pixelated. Always use high-res images and artwork.
   
   

4. Skipping Templates
   Every label shape has unique specs. Using a proper template ensures colours and layout stay intact.
   
   

5. Overlooking Bleed and Trim
   Without bleed, even perfect colours can be cut in the wrong place. Use the full template area to avoid errors in your food label design.
   

Simple Ways to Get Colour Right

• Start in CMYK: Set your file up in the right colour mode from the start.
  
  

• Use a Template: Most printers, including LabEX offer label-specific with correct margins, bleed and size.
  
  

• Export as a Print-Ready PDF: Don’t rely on screen file types like PNG or JPEG.
  
  

• Use a Pantone Colour Bridge Swatch Book: If colour precision really matters, compare your choices with physical ink samples. NB: Bear in mind there are always slight variances between swatches and colours produced by different printers. 

SOURCE: https://www.pantone.com/uk/en/products/graphics/color-bridge-guide-coated

• Run a Quick Pre-Upload Check: File format, colour mode, resolution, fonts, trim lines - confirm everything before uploading.
  
  

Getting this right upfront saves you time, money, and disappointment when it comes to product label design.

You don’t need to be a designer to get colour right. These tools simplify the process:

• Templates: Already set to CMYK and include bleed and trim zones.
  
  

• Design Software with CMYK Support: Use Canva (Pro) or Adobe Illustrator for better colour control.
  
  

• Pantone Colour Bridge Swatch Books: Useful for brands where colour consistency really matters.
  
  

• Preflight Checklist: Create a quick checklist to make sure you're uploading the right kind of file, at the right resolution, in the right mode.
  
  

Make Colour Problems a Thing of the Past

You don’t need to be a design expert to get your label colours right. You just need to know the few steps that matter most.

Set your file to CMYK. Use a proper template. Export as a high-res PDF. And if something feels unclear, ask before you upload.

These small choices make a big difference in your label printing results - and they’ll help your brand look just as good on the shelf as it does on screen.

Need help with your file? Reach out to the team at LabEX before uploading and get peace of mind.