So, you’ve decided to repaint your project car to match a special factory paint color. It’s the perfect shade for build, but how can you be sure you’re getting an exact match? After all, modern automotive paints are complex blends of resins, pigments, toners, effect particles, solvents, and additives. Factory “recipes” for each color spell out the exact ratios for all these components that must be precisely mixed.
There are numerous ways to find out what your paint color’s recipe is. The factory-issued names and their corresponding codes are often a good starting point. But they’re not the only way to get there. Modern scanners can also read and decode an existing finish to concoct a recipe. The method you choose, however, may depend on the specifics of your project and how you define an “exact” match. It may also affect your outcome.
Mixing to Code
Paint codes are the basis for most color match requests when painting a car. The manufacturer’s paint code can often be found on the vehicle’s data plate or VIN sticker. The location will vary from manufacturer to manufacturer, but a quick internet search will usually help you find it. The code may also look different for each manufacturer (e.g., “WA8555” for GM Black, or “L041” for VW Black).
A paint code tends to be a more reliable source than a paint name for getting an exact match. That’s because names can be vague and may vary from year to year or model to model. Having said that, each code may also have variants to account for slight factory batch differences, aging, regional plants, etc.
The correct code will result in a formula of resins, pigments, toners and additives that is unique to different paint mixing system. A PPG recipe for a given color may differ from that for BASF Glasurit, or Eastwood OEM Select, for instance. Proprietary database software for each system provides the exact gram weight of each toner/pigment, metallic, pearl, binder, and reducer.
Paints are mixed on a digital mixing scale. Each pigment or effect toner is dispensed in grams to the hundredth (0.01 g) precision. A typical formula may contain 8 to15 components for a single color. Once dispensed, either manually by a skilled painter or automatically using an industrial mixing machine, the weighed mixture is stirred to homogenize pigments and flakes. Reducer (solvent) is then added to achieve the correct fluidity.
Mixing from a Scan
Professional body shops often use a spectrophotometer to measure the actual color present on an existing finish. That’s because they’re often trying blend new paint with old paint, accounting for aging and wear. Even with a factory code on hand, scanning plays a vital role in accurately matching automotive paint colors. The highly calibrated optics can help discern complex finishes like metallics, pearls (interference pigments), and micas.
To get a reading, the area of the vehicle being scanned is cleaned thoroughly to remove wax, dust, and contaminants. A flat, undamaged section (usually near the fuel filler or door jamb) helps prevent distorted readings from scratches, fading, or dents. The spectrophotometer is placed directly against the paint surface. It uses multi-angle measurement (often 5 to 7 angles) to account for how light interacts with the base color metallic flakes (including size, orientation, and density), and pearlescent or mica particles (which change appearance with angle).
The device captures spectral reflectance data — the light intensity reflected at each angle across the visible spectrum (typically 400–700 nm). The spectrometer converts reflectance data into spectral curves, which describe how the paint looks at various angles. This data is uploaded to a color-matching software platform that compares the scanned data against a comprehensive database of known automotive paint formulas. It provides the closest color match, usually within a tolerance rating that indicates how perceptible the difference is to the human eye.
Once a formula is determined, the process of mixing paint is the same as doing so from a code.
Which Factory Paint Color Method is Best – Code or Scan?
We mentioned earlier the method you choose to get your paint recipe will depend a lot on the specifics of your project. If you’re doing a full repaint, especially a color change, going from code will probably get you the results you’re looking for. Fresh Hugger Orange or Plum Crazy Purple is going to look great if the whole car is the same color.
Generally speaking, a paint mixed to code is going to very closely resemble the original factory finish, regardless of what paint system is used. Never mind that you can line up three different Plum Crazy Chargers and see three different versions of that color.
If, on the other hand, you’re looking to seamlessly blend new paint onto an existing finish, scanning will almost certainly be the way to go. Combined with a paint code, this method will help get you closer to an exact match to older paint that may have faded, for instance. Or perhaps blend a previous repaint that may not have been 100% perfect. Even scanning can’t always guarantee perfection, however.
A skilled painter will use either of these methods as a starting point. They’ll begin by mixing up a small batch from the indicated formula and spraying out a sample for comparison. Form here, small adjustments can be made based on experience and human intuition. A bit less yellow toner or a touch more metallic to get the right glint.
In truth, color matching is an inexact science enhanced by a bit of imprecise art. The only way to get a 100% accurate match to a factory color is to have the factory paint your car. And that’s just not possible.