How to keep brand colors accurate in AI images
Image models do not measure color, so a hex code in a prompt is only a hint. Show the true color on your product reference photo, write each color as a name plus hex code, check the result with an eyedropper against a tolerance you set, and fix small shifts in editing software. Web images are sRGB; print needs your printer’s CMYK or spot-color spec.
Why your red comes out orange
An image model predicts what a photo of your scene should look like. It has no color meter, and it takes color cues from three places. Any of them can pull a red toward orange.
- The reference photo. If you shot the product under warm indoor bulbs, the model sees an orange-red and copies it.
- The light you describe. Golden hour, candlelight and warm tungsten color everything in the frame, the product included.
- Grade words. A film stock, a "vintage" look or a named color grade shifts every color at once.
Neither Google nor OpenAI says a color written in a prompt will come out exact. Google’s and OpenAI’s prompting guides for their image models, checked in September 2026, do not mention hex codes at all; OpenAI’s asks you to name colors in words.
Write each color as a name plus a hex code
A hex code such as #B3122E is an exact color in sRGB, the standard color space of the web. A designer can check it, and a model treats it as a hint. Pair every hex with a color name the model knows, and say where that color goes.
| Vague | Better |
|---|---|
| "Brand red" | "Deep cherry red #B3122E, on the cap only" |
| "#1D3B2A" | "Dark forest green #1D3B2A walls" |
| "Our blue" | "Faded Sky Blue #B0C4DE threads inside the stripes" |
| "Warm browns" | "Rich cocoa #3E2015 grading out to cocoa dust brown #B07D46" |
| "White background" | "White surface #FFFFFF" |
Those prompts listed the palette as names plus hex codes and named the background with its hex. The trouser job’s prompt also tied color to the reference in so many words: "Colors stay exactly true to the flat-lay, never shifted, never saturated." Record the palette once in your visual DNA and copy the same lines into every prompt.
Put the true color on the reference photo
The model copies what it sees in the product photo, color included. Google’s current models keep up to 10 object references faithful on Nano Banana 2 and up to 6 on Nano Banana Pro, and your product photo should be one of them. Make that photo right before it becomes a reference.
- Shoot the product under one kind of light, such as daylight from a window. Window light plus warm bulbs puts two color casts on one product.
- Put a gray card, a card printed in a known neutral gray, in one test frame, and set the white balance from it in your photo editor.
- Hold the real product next to your screen and compare. Fix the photo before you use it.
- If one color must be exact, add a flat swatch photo: the product’s colored surface filling the frame, evenly lit. Say in the prompt that it is the color reference.
More on shooting references in how to photograph your product so AI gets it right.
Check the result with an eyedropper
- Open the render at 100%.
- Sample a flat area of the color in even light, away from highlights and shadows.
- On a Mac, use Digital Color Meter: it averages every pixel inside its aperture, which evens out texture, and you can set it to show sRGB values. On Windows, PowerToys Color Picker (Win+Shift+C) copies the color as a hex code by default. Photoshop and Figma have eyedroppers too.
- Compare the result with the brand hex. If you need a number, use a color-difference tool that reports Delta E (ΔE). The ΔE formulas were designed so that a difference of 1.0 is about the smallest a person can notice.
- Agree a tolerance with your brand team: tighter for the product than for the background.
| Where the color appears | How strict to be | If it is off |
|---|---|---|
| The product and its packaging | Strict | Correct it in post, or render again |
| Logo and label | Exact | Paste the real artwork or the real packshot over the render |
| Brand ground or backdrop | Close | Correct it in post |
| Props | Loose, as long as they stay in the palette | Leave it or retouch it |
| Skin | No color cast, and the same across the set | Neutralize the light, then render again |
Fix small shifts in post
If the product is right in shape and only the color is off, correct it instead of rendering again. In Photoshop, a Hue/Saturation adjustment limited to one color range, or a Selective Color adjustment, moves one hue without touching the rest; GIMP’s Hue-Saturation tool works the same way. Mask the adjustment to the product so the background does not shift with it.
Render again when the color error comes with a shape error, or when the wrong color also changed the light, for example a red cap that throws an orange reflection onto the table. For logos and labels that must be exact, see why AI changes your product.
Screen color and print color
A hex code describes a screen color. Browsers treat colors written in hex, and images with no color profile, as sRGB, so export web images in sRGB; the sRGB standard itself is IEC 61966-2-1. File types and sizes for the web are in the best file format and size for product images.
Print works differently. Ink on paper uses CMYK (cyan, magenta, yellow and black), and CMYK color changes with the paper and the press: the International Color Consortium registers separate printing conditions for coated paper, uncoated paper and newsprint. Ask your printer which condition they print to, and let them convert your sRGB files.
Packaging and strong brand colors often use spot inks, such as Pantone colors, mixed to one exact color instead of built from four inks. Many Pantone spot colors cannot be matched exactly with the four CMYK inks. If your brand color is a spot ink, an AI image is a screen preview, and the printer matches the ink.
Questions people also ask
- What about metallic or pearlescent brand colors?
- No single hex describes them, because a metal finish changes with the light around it. Describe the finish in words, such as "brushed gold, warm, low shine", and show it on a reference photo lit the way the scene will be. Check the color in the flattest, most evenly lit area, and judge the shine by eye against the real product.
- Can I ask the model to fix the color in an edit?
- Yes, for small shifts: "change only the cap color to deep cherry red #B3122E; keep everything else the same". OpenAI’s guide recommends that pattern: say what to change, list what must stay, and change one thing at a time. Check the whole image afterwards, because edits can change details you meant to keep. For exact logo colors, editing software is more reliable.
- Why do the colors look different on my laptop and my phone?
- Screens differ in brightness, color range and settings such as night mode, so the same file can look different on each. Judge colors by their numbers with an eyedropper set to sRGB, and approve images on one calibrated screen.
Where Overs fits
Overs records each brand’s colors with hex codes as part of its visual DNA and sends your product photo to the image model as a reference, so the model sees the real color. On Pro and Team, a reviewer checks each photo against the references before you see it.
Free for 40 photos a month. The AI that makes the photos is billed separately, on your own key, with no markup from Overs.
Sources
- W3C: CSS Color Module Level 4 (hex and untagged images are sRGB)
- International Color Consortium: sRGB in the Three Component Color Encoding Registry
- International Color Consortium: CMYK Characterization Data
- Apple Support: Digital Color Meter User Guide for Mac
- Microsoft Learn: Color Picker utility in PowerToys for Windows
- Wikipedia: Color difference (Delta E)
- Wikipedia: Pantone (spot colors, CMYK and sRGB)
- Google AI for Developers: Nano Banana image generation
- OpenAI: Image prompting, GPT Image 2.5 prompting guide