How Paint Colour Matching Works: Paint Codes, Samples and Spray-Outs Explained

When somebody asks for an 'exact paint match', there are two very different jobs hidden inside that sentence. Sometimes the correct answer already exists as a recognised colour code. Other times the only reliable reference is the physical surface in front of you.

Route 1: match from a recognised colour code

Automotive OEM codes, RAL colours, British Standard references and manufacturer coating codes give the paint mixer a defined starting point. This is usually the cleanest route when the original specification is known.

For cars, a registration can help identify the vehicle and narrow the likely factory palette, but it should not be treated as proof of the exact paint formula on its own. Confirm the OEM paint code where possible, especially when several variants were offered in the same colour family.

Use our Automotive Paint & Colour Matching page to start the process.

Route 2: match from a physical sample

A physical sample becomes important when a coating has no known code, is historic, has weathered, or has been refinished previously. The sample should be representative of the colour you actually want to reproduce—not a corroded edge, heavily faded patch or contaminated surface if a better area is available.

Breakwells can assess customer samples and build a repeatable reference for suitable jobs. This is particularly useful for industrial equipment, heritage restoration, narrowboats and unusual finishes.

Why the original code and the current surface can look different

Paint changes in service. UV exposure, oxidation, chemical attack, polishing, repairs and substrate differences can shift appearance over time. That means an original factory code can be technically correct while a fresh application still looks different beside a 15-year-old panel.

This is one reason experienced matching starts with the use case: do you want the original specification, or do you need a practical match to the aged surface that exists today?

What is a spray-out card?

A spray-out is a controlled sample coated with the proposed paint before the final job. It allows colour, opacity, gloss and application behaviour to be checked on a real painted surface rather than judged from a monitor.

For custom and difficult matches, the spray-out creates a far better approval point than a digital swatch. If a colour needs adjustment, it is much cheaper to make that change before the main item is painted.

What about spectrophotometers?

Instrument readings can be a useful part of modern colour matching, particularly when comparing a sample against large formulation databases. They do not remove the need for judgement. Texture, metallic orientation, pearl effect, gloss, lighting and application technique can all influence how a colour is perceived.

Why screen colours are only a guide

Phones and monitors emit light; paint reflects it. Screen calibration, brightness and ambient lighting change what you see. Metallic and pearl finishes also change with viewing angle in ways a flat HEX or RGB swatch cannot reproduce.

Digital colour representation is indicative only. Paint is mixed using the manufacturer/OEM or confirmed colour reference, not the screen swatch.

How to give us the best information

• For automotive paint: registration, make/model/year and the OEM paint code if you can find it.
• For RAL or BS colours: provide the complete code, not just a colour name.
• For historic or unknown colours: provide a clean representative sample where practical.
• Tell us the substrate, intended use and finish required—gloss level matters as well as colour.

If the match matters, confirming the reference before ordering is the fastest route to confidence. Speak to the Breakwells team if you are not sure which route applies to your project.