Color Match - Sync Renders To Color Palette is a Blender add-on for achieving precise color matching within your renders. You pick a target color with a HEX code or color picker, set the X and Y coordinates and size of a target point on the render image, then right-click a color property in a material or compositor node and choose Assign to Color Match. Running it renders a small part of the image multiple times and optimizes the color in that area toward your target.
The algorithm is based on gradient descent, finding the minimum difference from the target value. Each iteration renders a portion of the image, calculates the error between the desired and actual color, and adjusts the RGB values to reduce it. A Step Size value controls how far each iteration moves, with smaller steps being more precise but slower to converge.
It operates on color properties from materials and compositor nodes, runs on both Cycles and Eevee, and matches regardless of the image's color space. It can't match colors unachievable by a single RGB change, and a small residual error remains, though more iterations reduce it. It's a GPL add-on compatible with Blender 3.4 through 5.0.