You approve your new logo on screen. It looks perfect: a deep, vibrant blue that feels confident and modern. Three weeks later, 2,000 business cards arrive and the blue has turned slightly purple, a bit muddy, and definitely not the colour you signed off on. There is a practical rundown of it online.

Nobody made a mistake in the design. The file simply moved from one colour system to another, and nobody defined what should happen in between.

This is the practical reality behind the CMYK vs RGB branding question. Most articles stop at “RGB is for screens, CMYK is for print”. True, but useless when you are holding a printed brochure that does not match your website. This guide goes further: why the shift happens, how to lock your brand colours across every medium, how to convert logo files correctly, and the specific mistakes that cost agencies and clients money at the printer.

The short answer first

If you only read one section, read this one:

• RGB (Red, Green, Blue) is for anything that emits light: websites, apps, social media, digital ads, presentations, video, email signatures, screens on trade show displays.
• CMYK (Cyan, Magenta, Yellow, Key/Black) is for anything printed with ink on a commercial press: business cards, brochures, packaging, stationery, magazine ads, catalogues.
• Pantone (spot colour) is for brand-critical print where exact consistency matters more than cost: logos, signage, premium packaging, corporate stationery.
• HEX is simply RGB written in a format developers and web tools can read. Same colour, different notation.

A serious brand does not choose between these. It defines all four in the style guide, so nobody ever has to guess or convert on the fly.

Why the two colour modes exist at all

RGB is additive light

Your screen starts black. Pixels emit red, green and blue light, and the more light you add, the brighter the result. All three at full strength produce white. This is called an additive model because you build colour by adding light.

Because light is being generated rather than reflected, RGB can reach colours that ink physically cannot: electric cyans, neon greens, glowing oranges, saturated purples.

CMYK is subtractive ink

Print starts with white paper reflecting nearly all light. Each layer of ink absorbs (subtracts) part of the spectrum. Cyan, magenta and yellow together theoretically make black, but in practice they produce a muddy brown, which is why black ink (K, for “key”) is added as a fourth plate for depth, text sharpness and shadow detail.

You are limited by physics: paper reflectivity, ink density, and how much liquid the sheet can absorb before it stops drying properly.

The gamut gap: the real reason colours shift

A gamut is the total range of colours a system can reproduce. The CMYK gamut is meaningfully smaller than the RGB gamut. When you convert an RGB file to CMYK, any colour outside the printable range gets pushed to the nearest achievable equivalent.

That is what happened to the purple business card. The blue existed in RGB but not in CMYK, so it was remapped and it lost energy in the process.

Aspect	RGB	CMYK
Model	Additive (light)	Subtractive (ink)
Channels	3 (R, G, B)	4 (C, M, Y, K)
Value range	0 to 255 per channel	0% to 100% per channel
White is	All channels at maximum	No ink (bare paper)
Gamut size	Larger, especially in bright saturated tones	Smaller, limited by ink and paper
Best for	Web, app, social, video, digital ads	Offset and digital press printing
File formats	PNG, SVG, WebP, JPG for web	PDF/X, AI, EPS, high-res TIFF
Notation used by	Developers (HEX), UI designers	Printers, prepress operators

Should a logo be designed in RGB or CMYK?

This is the most asked question on the topic, and the honest answer is more nuanced than the usual advice.

Design in RGB, but validate in CMYK from day one.

Here is the reasoning:

1. RGB gives you the widest working space and matches how you and the client will actually view the work during the process.
2. Most brand touchpoints today are digital, so RGB is the primary environment.
3. But if you never check the CMYK equivalent until the printing stage, you may fall in love with a colour that simply cannot be printed.

The professional workflow is to pick a candidate palette in RGB, then immediately soft proof it in CMYK and, ideally, print a test on the actual paper stock. If the colour collapses, adjust it before presentation, not after approval.

Colours that consistently disappoint in print

• Electric blues and royal blues: the classic offender, often shifting toward violet.
• Neon greens and limes: lose their glow and read flat.
• Bright oranges and corals: dull down noticeably.
• Vivid turquoise and cyan-teal: readable on screen, chalky in ink.
• Deep saturated purples: tend to go grey or brown.

If a brand absolutely needs one of these, the answer is a Pantone spot colour or an extended-gamut press process, not a CMYK approximation.

Where Pantone fits into CMYK vs RGB branding

Pantone (PMS) colours are pre-mixed inks rather than blends of four process inks. Instead of asking a press to build your blue from cyan and magenta dots, you hand the printer a specific ink recipe.

When Pantone is worth the cost

• Your logo appears on high-volume packaging where consistency between print runs is visible on shelf.
• Your brand colour sits outside the CMYK gamut.
• You need the same colour across paper, fabric, plastic and painted signage.
• The brand colour is a recognition asset in itself (think of the colours you can name a company from).

When Pantone is overkill

• Small runs on digital presses, which cannot print spot colours anyway and will simulate them in CMYK.
• Budget-sensitive projects where each additional plate adds real cost.
• Brands that live almost entirely online.

Important nuance most guides skip: a Pantone-to-CMYK conversion is an approximation, and a Pantone-to-HEX conversion is a different approximation. Do not assume the automatic value your software offers is the best available match. Pantone publishes its own bridge values, and your printer can advise on the closest achievable build for your chosen stock.

How to define brand colours properly in a style guide

This is where most brand guidelines fail. They list a HEX code and stop. Then a print supplier converts it automatically, a social media freelancer eyedrops a screenshot, and within a year the brand has five slightly different versions of its own colour.

A complete colour specification includes five data points per colour:

Field	Example	Used by
HEX	#1B4DE4	Web developers, CSS, design tools
RGB	27 / 77 / 228	Video, presentations, screen graphics
CMYK	88 / 70 / 0 / 0	Print suppliers, prepress
Pantone (coated + uncoated)	2727 C / 2727 U	Packaging, signage, merchandise
RAL or vinyl reference	RAL 5005 (nearest)	Signage, paint, vehicle wraps, interiors

Add these three rules to the guide as well

• Specify coated and uncoated Pantone separately. The same ink looks different on glossy versus matte stock, and “use 2727” is not enough information.
• State the intended print standard. For most commercial work in Europe, that means a Fogra-based profile such as Coated FOGRA39 or PSO Coated v3; in North America, a GRACoL-based profile. Without this, “CMYK” is an incomplete instruction.
• Forbid on-the-fly conversion. One line in the guide, such as “Never convert brand colours automatically. Use the values in this document only”, prevents the majority of drift.

Converting logo files correctly: a step-by-step walkthrough

Delivering a logo package is not just exporting a PNG. Here is the workflow we use on brand projects.

Step 1: Build the master in vector

Your source file should be vector (Illustrator, Affinity Designer, Figma with proper vector export) with the logo built on clean paths, expanded strokes where appropriate, and no stray effects that behave unpredictably in conversion.

Step 2: Create two colour masters, not one

Do not maintain a single file and convert it every time. Maintain:

• An RGB master using the sRGB profile, with brand colours set to the exact HEX values in the guide.
• A CMYK master using your target print profile, with brand colours set to the exact CMYK values in the guide.

Both files are hand-checked. Neither is a machine translation of the other.

Step 3: Define swatches as global, and spot where relevant

Set brand colours as global swatches so a single edit updates every instance. For print files that will use spot inks, define the Pantone colours as actual spot swatches, not as CMYK builds named after a Pantone number. Printers separate plates from swatch type, not from swatch names.

Step 4: Soft proof before you commit

Use your software’s proof setup to preview the file under the target print profile, and turn on gamut warning to see exactly which areas cannot be reproduced. This is the moment to make artistic decisions, not the moment the printer calls you.

Step 5: Export the delivery package by use case

Use case	Format	Colour mode
Website, app	SVG, plus PNG and WebP fallbacks	RGB (sRGB)
Social media profiles	PNG at required pixel sizes	RGB (sRGB)
Office documents, slides	PNG with transparency	RGB (sRGB)
Commercial print	PDF/X-4, plus EPS or AI on request	CMYK or spot
Large format, signage	Vector PDF or EPS	CMYK or spot, ask the fabricator
Embroidery, merchandise	Vector, single-colour versions	Spot / thread reference

Step 6: Include the awkward versions

A complete package also contains a one-colour black version, a one-colour white (knockout) version, and a version approved for use on dark backgrounds. These prevent someone improvising when your full-colour logo does not work on a black tote bag.

The most common colour-shift mistakes when sending files to a printer

These are the errors we see most often, roughly in order of frequency.

1. Sending an RGB file and hoping for the best

The printer’s system will convert it, using its default profile and its own rendering intent. You have handed away control of your brand colour. Convert deliberately, or supply values the printer must hit. Much the same conclusion turns up on thelittlelogolab.com.

2. Letting a design tool auto-convert HEX to CMYK

Automatic conversion is mathematically valid and aesthetically unreliable. A HEX that converts to a technically correct CMYK build can still look wrong. Always eyeball the result and adjust manually if needed.

3. Using rich black incorrectly, or not at all

100% K alone often prints as a washed dark grey on large areas. A rich black build (commonly something in the region of 60/40/40/100, though ask your printer for their preferred recipe) gives depth. But rich black under small body text causes registration problems and fuzzy edges. Rule of thumb: rich black for large solid areas, 100% K for small text.

4. Ignoring total ink coverage limits

Stack all four channels near maximum and you exceed the press’s total ink limit. The result: slow drying, set-off between sheets, and colours that go dense and muddy. Most coated stock profiles cap total coverage around 300% to 330%.

5. Mixing colour modes inside one document

A brochure with some RGB images, some CMYK images, and a mix of swatch types is an invitation to inconsistency. Standardise the entire document before export.

6. Naming a CMYK swatch after a Pantone colour

Calling a process build “PMS 2727” does not make it a spot colour. If you need a spot plate, define a spot swatch. If you do not, do not confuse the prepress operator with the name.

7. Judging colour on an uncalibrated screen

If your monitor has never been calibrated, everything above is guesswork. You cannot make reliable colour decisions on a display you have not measured, and no amount of correct file setup compensates for that.

8. Skipping a physical proof on brand-critical jobs

For packaging, a first business card run, or anything printed in high volume, request a hard proof on the actual stock. It costs a fraction of a reprint.

9. Forgetting that paper changes everything

The same CMYK values print differently on gloss coated, matte coated, uncoated and recycled stock. Uncoated paper absorbs more ink and generally produces softer, slightly darker results. If your brand uses uncoated stationery, specify values for it.

What about Canva, Figma and other browser-based tools?

A frequent question, so worth addressing directly.

• Canva works natively in RGB. It offers a CMYK print PDF export on paid plans, but the conversion is automatic and you have limited control over the profile or the resulting values. It is fine for internal documents and low-stakes printing. It is not adequate for brand-critical packaging or corporate stationery.
• Figma is an RGB environment by design, built for interface work. It is excellent for digital brand assets and a poor choice as a print production tool.
• Professional print production still lives in Illustrator, InDesign, Affinity Publisher or equivalent, where you control profiles, separations, ink limits and spot channels.

If a brand is being built in a browser tool only, the print side of the identity is being left to chance.

A realistic expectation to set with clients

Print and screen will never match perfectly. One is reflected light on paper, the other is emitted light through glass. The goal is not identity, it is controlled consistency: a colour that reads as unmistakably the same brand in both environments, with differences that are deliberate rather than accidental.

Saying this early in a project saves an uncomfortable conversation later.

Quick reference checklist

1. Design in RGB, soft proof in CMYK before presenting.
2. Define HEX, RGB, CMYK, Pantone coated and Pantone uncoated for every brand colour.
3. State the target print standard in the style guide.
4. Maintain separate RGB and CMYK logo masters, hand-tuned.
5. Use global swatches, and real spot swatches when spot inks are needed.
6. Export PDF/X-4 for print, SVG and PNG for digital.
7. Include one-colour and reversed logo versions.
8. Respect ink coverage limits and rich black rules.
9. Calibrate your display.
10. Order a hard proof on the real stock for anything important.

FAQ

Should I use RGB or CMYK for my logo?

Both. Create and store an RGB version for all digital use and a separately tuned CMYK version for print. The master artwork should be vector so either can be produced without quality loss. Add Pantone references if the logo will appear on packaging, signage or merchandise.

Why use CMYK instead of RGB for printing?

Presses lay down cyan, magenta, yellow and black ink. CMYK values describe exactly how much of each ink to apply, so they map directly to what the machine does. An RGB value describes light output, which a press cannot use without converting first, and that conversion is where unpredictable colour shifts occur.

Does RGB or CMYK print better?

CMYK prints more predictably, because it is the language of the press. RGB files can produce acceptable results on some modern digital presses and inkjet devices that internally handle wide-gamut input, but you are trusting someone else’s conversion settings. For brand work, CMYK or spot gives you control.

Does Canva design in RGB or CMYK?

Canva works in RGB. Paid plans allow a CMYK PDF export, but the conversion happens automatically and you cannot fine-tune profiles or individual values. Use it for internal or casual print, not for brand-critical production.

Is HEX the same as RGB?

Yes, functionally. HEX is a six-character way of writing the same three RGB channel values in hexadecimal. #FFFFFF and RGB 255/255/255 are the same white. HEX exists because it is compact and convenient in code.

Why does my brand blue look purple when printed?

Vivid blues frequently sit outside the CMYK gamut. During conversion, the colour is remapped to the nearest printable equivalent, and because blue is built from cyan plus magenta, the magenta tends to dominate visually. Fixes: adjust the CMYK build manually, reduce magenta, or specify a Pantone spot ink.

Can I convert CMYK back to RGB?

Technically yes, but it will not restore the original vibrancy, since the data lost during the first conversion is gone. Always keep your original RGB master rather than converting back and forth.

How many brand colours should a style guide define?

A common structure is one to two primary colours, two to three secondary colours, a small set of neutrals, and defined values for text and background use. What matters more than the count is that every single one is documented in all relevant colour systems.

Need your brand colours locked down across print and digital?

Getting CMYK vs RGB branding right is not a design preference, it is production discipline. If your logo files, style guide or print specifications are not giving you consistent results, we can audit your current assets, rebuild your colour system properly, and deliver a package that works the same way for a web developer, a printer and a signage fabricator.

Get in touch with Casta Agency to discuss your brand identity project.