This site seems to speciliase in getting resources (genearally free) from users and then display them in a blog format utilising their specialist software that pulls the color palettes from the image automatically.

Be inspired by the most popular colors, palettes, gradients, and patterns in our database. Discover - Art & Design Inspiration at ColRD.com

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Permission is granted to make use this website, applications, and services to download graphic primitive resources to your computer. All resources on ColRD are contributed by individuals, and have various licenses depending on the individual’s wishes. These licenses are listed on the individual graphic primitive pages. Any graphics created on ColRD.com or with software owned by ColRD will use a CC0 license.