Flowfiles ← Color Palette Extractor

Color Palette Extractor Without Upload

Private · No Server · No Account · Your Images Stay on Your Device

Extract color palettes from sensitive or confidential images without sending them anywhere. This tool uses the Canvas API and JavaScript to process every pixel locally inside your browser tab. There is no backend, no cloud storage, no analytics on your files. The image never moves beyond your own screen.

Open the extractor and start immediately — no account, nothing stored on any server.

Open the Color Palette Extractor →

Why a no-upload color extractor matters

Most online image tools route your file through a server — which means it gets stored, logged, and potentially retained for model training or caching. For unreleased product photos, client work, medical imagery, or any image you would prefer to keep off the internet, a browser-only tool is the only safe option. The Flowfiles extractor uses the Web Canvas API's getImageData() method to read pixel values directly in memory. Nothing is serialized to a network request. You can confirm this with your browser's Network tab — zero image-related outgoing requests during extraction.

/* How browser-side extraction works — no server involved */ const canvas = document.createElement('canvas'); const ctx = canvas.getContext('2d'); ctx.drawImage(img, 0, 0, 300, 300); const { data } = ctx.getImageData(0, 0, 300, 300); // data is a Uint8ClampedArray of [r,g,b,a, r,g,b,a, ...] // K-means runs on this array — no network call made

Frequently asked questions

How does browser-side color extraction work without a server?

When you drop an image, the browser reads it via the File API and draws it onto an offscreen HTML Canvas element. JavaScript then reads the pixel data from the canvas using getImageData(), processes it with K-means clustering, and returns the palette — all without any network request.

Is my image truly private?

Yes. The image never leaves your device. No network request is made during extraction. You can verify this by opening your browser's Network tab in DevTools before dropping an image — you will see zero outgoing requests related to the file.

Does the tool work offline?

Once the page is loaded, the color extraction works entirely offline. The only network dependency is loading the page itself and its stylesheet. The pixel processing is pure JavaScript with no external API calls.

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