Generate cohesive color themes for presentations with primary, accent, and background palettes.
The guide
You pick one color - usually a brand color or the hero hue of your topic - and this tool derives the rest of the palette around it: a primary for titles and headlines, an accent for highlights and data, and background plus text colors that work as a pair. The output is meant to be used before you build slides, so charts, callouts, and dividers all draw from one family. The surprise is how much rides on the seed: two themes differing only in seed color read as completely different decks, so choosing that one color is the real design decision.
The theme comes as roles, not a flat list of swatches: the primary carries the main elements, the accent is reserved for emphasis, and the backgrounds pair with text colors that sit on top of them. The structure matters because a color that works as a fill is often unreadable as text, and a palette without assigned jobs leaves slides where nothing is the point.
The generated colors share a family, which is what makes a deck look intentional. But cohesion alone does not guarantee contrast: a harmonious pair can still fail when the audience is ten rows back in a bright room. Treat the theme as a starting set and verify the extreme pairs - darkest text on lightest background, accent on both backgrounds - with a contrast checker before the talk.
Choose your brand color as the seed - the theme is built around the seed you pick, so the primary carries it. The accent and background are generated to sit with it, not matched to a brand book, so where your brand fixes exact values, override the generated hex codes with the approved ones and keep the rest.
Projectors and bright meeting rooms reduce contrast that looks fine on a laptop, especially for mid-tone colors and thin text. The palette itself may be fine - the fix is to verify the extreme pairs with a contrast checker and pick the higher-contrast pair for anything shown from a distance.
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