How Paint Matching Works (and Why Colours Differ From the Tin)

Where the paint code comes in

Manufacturers give each colour a code, usually shown on a plate or sticker somewhere on the car, such as inside a door shut, under the bonnet or in the boot. Your handbook or the registration details can help you track it down. That code identifies the original formula and is the sensible place to begin.

But one code can have several variants. Factories sometimes used slightly different batches or suppliers over the production life of a model, so the code alone will not always give a perfect result. A painter will often check the actual paint on the car against the recipe.

Why your car's colour has moved on

Paint changes with age. Sunlight bleaches pigments, weather dulls the surface and years of washing and polishing wear the top layer. A ten-year-old car does not sit quite where the factory formula would put it, so matching a fresh batch directly to the code can leave an obvious patch.

This is why experienced painters compare the mixed colour against the car itself and adjust the tint. Small changes to the mix can bring it back into line with what the paint looks like today, not what it looked like when it left the plant.

• Sun exposure fades red and other strong colours more visibly
• Different panels can age differently, such as roof and bonnet
• Previous repairs may already be slightly off the original shade
• Dirt and oxidation can hide the true colour

Solid, metallic and pearl finishes

Solid colours are the simplest to match because they have no flake. Metallic paints contain tiny aluminium particles that catch the light, and how they lie in the paint changes the look depending on how it is sprayed. Pearl and tri-coat finishes add another layer of complexity because the effect depends on several coats.

That is why spray technique matters as much as the colour mix. Two identical formulas applied differently can look different, especially in metallic paints, and a painter may need to adjust the gun settings or the spraying pattern to get the effect to line up.

Spray-out cards and checking the match

A common way to check is to spray a test card, let it dry and hold it against the car in good light. Painters compare it from different angles, because metallic and pearl colours can shift as you move around the vehicle. If it is not right, the mix is tweaked and tested again.

This is a patient, stage-by-stage job. A perfect match on the first attempt is not something every car allows, and that is a normal part of the process.

Blending into neighbouring panels

Even a good match can show at the edge of a repair. To avoid that, the painter blends the new colour gradually into the adjoining area, so the eye never finds a hard line. On many repairs, the adjacent panel is partly painted too, with the new colour fading out across it.

Blending is one reason a repair can involve more than the damaged part itself. It is also why a partial respray can look seamless when done well.

Lighting and judging the result

Colour is easy to misjudge. Under fluorescent workshop lights, a match can look perfect and then appear slightly different in bright sun or on an overcast Tyneside morning. Experienced painters check in more than one kind of light, and so should you when you collect the car.

At Banks of the Tyne in Hebburn, paint matching is part of our paintwork service. If you spot anything you are not happy with, take the car out into daylight and talk it through with us.

Frequently asked questions