RGB VS CMYK VS PMS: Difference, Printing Accuracy, Advantages and Limitations

RGB, CMYK and PMS are colour systems designed for different purposes in design and printing. RGB is an additive model that uses red, green and blue light for digital screens, offering a wide colour range but limited print accuracy. CMYK is a subtractive ink-based model used for full-colour printing, where colours depend on inks, paper and press conditions. PMS (Pantone) uses premixed spot inks to achieve highly accurate and consistent brand colours across different printers and materials. Each system differs in gamut, workflow and predictability, so choosing the correct model is essential for colour accuracy. In practice, designers use RGB for screens, CMYK for process printing, and PMS when exact colour matching is critical.

What is RGB?

RGB is an additive colour model that forms colour by combining red, green and blue light on digital displays such as monitors, smartphones and tablets. It uses three primaries with numeric intensity values that control hue and luminance. It defines on‑screen colour and acts as the starting point for soft proofs and digital previews. Designers build UI, motion and web assets in RGB for frames, icons and layouts, then convert those assets to print modes later. Wide‑gamut RGB spaces reduce loss during conversion when they align with print profiles. Accuracy depends on display calibration and ambient light. Colour shifts appear if an RGB source is mapped to print without colour management. 

What is CMYK?

CMYK is a subtractive process that forms colour by placing cyan, magenta, yellow and black inks onto coated paper, uncoated stock or corrugated board. The four inks combine through halftone or stochastic screens to form continuous‑tone images on print substrates. The system shows a smaller gamut than RGB, and print results shift with dot gain, ink order and ink set. CMYK suits full‑colour work such as magazines, brochures and posters. Conversion from RGB to CMYK applies gamut mapping and a rendering intent to compress or clip colours that sit outside the print range. Overprint settings influence edge behaviour during this conversion if objects stack or overlap in the artwork.

What is PMS (Pantone Matching System)?

PMS uses premixed and named ink swatches that keep spot colours consistent on different presses and substrates such as packaging, corporate identity items and promotional print. It sets a fixed reference so a Pantone number links to a specific ink recipe. It cuts guesswork when a brand colour must stay exact. It adapts to expanded Pantone guides that support digital‑to‑print checks and to press steps such as overprint control used in short runs or metallic and fluorescent work. Each added spot ink reduces press flexibility and raises setup cost, yet the same spot ink, applied by different vendors, aligns more closely with the intended swatch than a CMYK simulation.

How Do RGB, CMYK and PMS Differ in Construction and Function?

RGB mixes light from three channels, CMYK places subtractive inks in screened layers, and PMS uses premixed spot pigments with fixed recipes. Each model sets its own gamut limits, workflow role and match accuracy. The table below lists clear distinctions for reproduction, workflow and match control:

The comparison shows how each system follows a distinct construction method that affects gamut size, print behaviour and match reliability. The key point lies in model choice, because model choice dictates achievable colour accuracy in packaging workflows.

How Do RGB, CMYK and PMS Affect Printing Accuracy and Colour Matching?

RGB, CMYK and PMS affect printing accuracy and colour matching in the following ways:

RGB Accuracy on Screens and Limits in Print

RGB accuracy depends on calibrated light‑emitting displays that form colour through red, green and blue channels. RGB accuracy controls on‑screen previews for packaging mock‑ups, icon sets and layout frames. Colour drift appears after conversion to ink because saturated RGB hues sit outside the CMYK gamut. ICC profiles translate luminance‑based values into ink densities; mismatched profiles generate abrupt shifts in blues and greens. Soft proofs help designers predict these shifts if a monitor matches a D50 reference booth.

CMYK Accuracy on Press and the Impact of Substrate Behaviour

CMYK accuracy depends on ink density, dot gain, screening choice and substrate absorption. CMYK accuracy varies across coated stock, uncoated paper and corrugated board. Porous fibres absorb more carrier fluid and darken midtones. Press operators adjust cyan and magenta densities through inline measurement; deviations alter neutrals first. Halftone screens increase contrast shifts in shadows if dot gain rises above tolerance. Hard proofs expose these variables before a packaging run proceeds.

PMS Accuracy for Brand-critical Colours in Packaging

PMS accuracy follows fixed ink recipes that lock hue, saturation and density for brand colours. PMS accuracy supports labels, cartons and sleeves that require repeatable hue across 3 or more vendors. Overprint controls matter because a spot ink sitting under or over a CMYK element alters reflectance. Pantone swatches exist in coated and uncoated variants; a brand team checks printed sheets against both if packaging spreads across different substrates. ΔE values quantify deviation between a target swatch and a press sheet; ΔE under 2 keeps brand consistency for most packaging categories.

Cross-system Accuracy from File Preparation and Proofing

Cross-system accuracy follows a sequence that starts with source-space setup, moves through profile assignment and ends with on-press verification. Cross-system accuracy improves when designers convert artwork to CMYK or nominate PMS inks before export. Overprint previews reveal hidden stacking issues around dielines or varnish layers. Soft proofs expose gamut compression after conversion; contract proofs verify ink behaviour on the exact packaging substrate. A controlled viewing booth avoids metameric shifts that confuse approval teams.

When Should RGB, CMYK or PMS be Used in Packaging?

Choose RGB for screen‑first delivery, CMYK for four‑colour print, and PMS for exact spot‑colour matches across vendors and substrates. Use RGB if the artwork stays on screens and requires a wide‑gamut look for items such as web pages or video frames. Choose CMYK if the print run uses four‑colour process on an industrial press and preserves photographic detail for items such as magazines or brochures. Select PMS if a brand or product colour must match across printers and substrates and if colour drift is unacceptable for items such as logos or packaging. 

Add CMYK plus one or two PMS spot inks, if photographic images and exact brand colours appear together and if the press line keeps spare ink units. Check overprint settings during artwork preparation, if spot inks interact with CMYK layers, because incorrect stacking causes shifts on press and inconsistent edges, according to the context of overprint controls.

What are the Advantages of RGB, CMYK and PMS?

The advantages of RGB, CMYK and PMS are discussed below:

1. RGB

Wide-gamut Previews for Packaging Colours

RGB covers a broader colour range than CMYK, so RGB previews display saturated hues that guide designers before conversion. Wide-gamut spaces show intense reds and greens that later compress during print conversion, which helps designers judge the impact of mapping early in the workflow.

Supports Accurate Soft Proofs for Dielines and Overprint Checks

RGB supports controlled soft‑proof previews that expose stacking and overprint issues before artwork moves to CMYK or PMS modes. Overprint behaviour around dielines, varnish layers or knockout areas becomes visible on calibrated displays that follow D50 viewing conditions.

Keeps Edit Flexibility Before Print Conversion

RGB files preserve adjustment latitude for tonal edits, gradients and photographic elements because RGB channels respond predictably to exposure and saturation changes. This reduces cumulative loss when designers prepare alternate layouts for packaging if different print vendors require separate CMYK profiles.

Reduces Early Colour Clipping During Artwork Creation

RGB reduces early gamut clipping because edits occur in a space that holds more saturated values than process inks. This delays compression until final conversion, so colour accuracy improves for packaging assets that pass through multiple revisions before export.

2. CMYK

Photographic and Gradient Control

CMYK produces continuous‑tone images through screened dots that create short tonal steps across photographs and gradients. Screen angles and dot geometry influence contrast on coated and uncoated substrates, if surface absorption shifts ink density. This steadies print behaviour across long packaging runs.

Cost Stability in Repeat Runs

CMYK keeps production cost stable because each run uses the same four ink units. Press crews charge cyan, magenta, yellow and black once, which reduces prep time for 1,000‑piece and 50,000‑piece batches. UK manufacturers depend on this stability when planning repeat packaging cycles.

Press and RIP Alignment

CMYK aligns with prepress RIPs that apply trapping, overprint rules and colour‑profile conversions. Operators control ink limits, dot gain and sheet calibration across offset, flexo and digital equipment. This reduces mapping faults if an RGB asset reaches a RIP without conversion.

ICC and Proofing Control

CMYK integrates with ICC profiles that govern gamut mapping from RGB sources. Hard proofs reveal density and neutral balance on carton board or kraft liners. Soft proofs display compression earlier if the artwork uses saturated hues outside the CMYK print range.

Overprint Consistency on Press

CMYK maintains consistent overprint behaviour when dielines, varnish layers or spot inks sit above or below the four‑colour stack. Overprint preview checks layer order so presses avoid halo edges or tonal shifts in packaging runs. Notes in artwork guides emphasise this step because mis‑stacking causes the bulk of prepress faults.

3. PMS

Fixed‑recipe Predictability

PMS supplies fixed ink formulations that anchor hue, saturation and density to printed swatches. Printers check drawdowns, density and trapping against Pantone guides during make‑ready, if packaging demands narrow tolerances across repeat batches.

Metallic and Fluorescent Options

PMS supports metallic and fluorescent pigments that inks cannot form. Metallic flakes raise reflectance on cartons and sleeves, and fluorescent pigments increase daytime visibility on safety labels, if artwork requires colours outside the CMYK gamut.

Vendor‑to‑vendor Consistency

PMS increases consistency across suppliers because each vendor loads the same premixed spot ink. Press crews verify behaviour through drawdown comparisons and ink‑film checks, if cartons, labels and sleeves come from multiple UK plants.

Stable Overprint Behaviour

PMS supports stable overprint and trapping behaviour because spot inks keep predictable opacity and transparency traits. Overprint preview exposes edges around dielines, varnish zones or small text, if stacking order creates halo artefacts before press.

Swatch‑based Brand Verification

PMS enables direct comparison against coated and uncoated guides under D50 lighting. Brand teams read ΔE values between the sample and reference swatch to confirm match accuracy, if packaging spans substrates that absorb ink at different rates.

What are the Disadvantages of RGB, CMYK and PMS?

The disadvantages of RGB, CMYK and PMS are explained below:

1. RGB

Non‑printable Primaries in RGB

Non‑printable primaries in RGB fall outside CMYK and PMS gamuts, so saturated hues collapse during conversion on packaging workflows. RGB builds colour with emitted light, and its most intense blues, greens and neon tones exceed ink capacity. Gamut mapping compresses these values into smaller ranges if a designer exports artwork without checking a soft proof. Conversion reduces vibrancy on coated and uncoated stocks because ink absorption restricts reflectance. Overprint previews expose clipped edges around dielines where bright RGB objects overlap process inks.

Device Dependence in Reproduction

Device dependence in RGB reproduction leads to inconsistent previews across monitors, phones and tablets. Each display applies its own backlight, tone response curve and white point, so a packaging mock‑up shifts between devices. Calibrated workstations reduce this shift if profiles match a D50 booth used for print approval. Variations rise on consumer screens that boost saturation artificially. Designers check overprint behaviour on a profiled monitor because incorrect stacking hides real print interactions that appear only after CMYK or PMS conversion.

2. CMYK

Gamut Limits that Restrict Saturated and Corporate Colours

CMYK shows gamut limits that compress saturated hues and specific corporate colours. Deep oranges, vivid purples and neon‑leaning tones shift during conversion because process inks cannot reproduce high‑chroma values on coated or uncoated substrates. Soft‑proof checks reveal these shifts early if designers preview artwork against the target ICC profile.

Process Variability from Press Conditions and Substrate Absorption

CMYK prints change through press variability, ink sets and substrate absorption. Density drift appears when ink films vary across runs or when paper fibres pull carrier fluid into the sheet. Coated stock reflects more light and maintains contrast; uncoated stock absorbs more ink and darkens midtones. Variation increases between suppliers if each site runs different screening or ink inventories.

3. PMS 

Extra Cost From Separate Ink Runs and Custom Mixes

Spot‑ink production adds cost because each colour sits in its own unit, uses an individual wash‑up cycle and requires a mixed batch before make‑ready. Flexo and litho lines add 6 to 12 minutes per extra unit, if operators purge previous ink films or check viscosity. Variable‑data runs slow further because plate swaps already interrupt the sequence. Packaging workflow notes describe measurable delays on presses with limited stations when artwork contains two or more spot colours, metallic tones or fluorescent inks.

Substrate Behaviour Differences that Reduce Match Accuracy

Spot inks respond to coated, uncoated and fibre‑dense boards in distinct ways because pigment load and ink‑film thickness change how light reflects. Coated sheets hold a tighter ΔE because the surface restricts absorption. Uncoated stocks draw carrier fluid into fibres and mute chroma. Fibre‑heavy liners used in transit packaging darken midtones further. Print teams compare drawdowns to reference swatches under D50 lighting, if the olerance sits under ΔE 2 for brand cartons or sleeves.

Overprint Interactions During Artwork Preparation

Spot‑ink opacity alters how colours stack with CMYK layers, so overprint preview becomes essential before export. Halo edges appear around dielines, varnish windows or thin rules, if a spot sits above a screened process build. Notes in overprint guides list stacking order errors among the most common prepress faults when designers convert late from RGB or CMYK. Correct sequencing removes mismatches that occur on flexo or litho presses with strong ink‑film laydown.

Limits in Image‑heavy Artwork

Spot systems fail to form continuous‑tone images because they rely on single‑ink films rather than screened mixes. Gradients, skin tones and multi‑tone photographs collapse when replaced by discrete spot units. Expanded swatch sets cover metallic and fluorescent regions, yet they do not replace CMYK for smooth tonal transitions. Spot colours, therefore, remain confined to logos, panels and high‑chroma accents if the artwork depends on photographic detail across packaging panels.