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🖤 Image Grayscale

Convert images to black & white, grayscale, sepia, or threshold in your browser with 11 algorithms, drag before/after slider, and scene presets

🔒 In-browser processing — your images are not uploaded by the tool

Drop an image, click to choose, or paste with Ctrl+V

Supports JPG / PNG / WebP. Max 25 MB. Local processing.

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Image Grayscale / Black & White tool with 11 algorithms (BT.709 / BT.601 / Average / Desaturate / Max / Min / R / G / B channels / Gamma-correct luma / Channel mixer / Sepia / Duotone / Threshold with Otsu auto + Floyd-Steinberg dithering), 6 scene presets (photocopy / ID B&W / logo mono / high-contrast comic / vintage sepia / newsprint), drag-to-compare before/after slider, compare-all thumbnails grid, brightness / contrast / gamma post-process, PNG transparency preserved, JPEG auto-white fill, WebP optional alpha, four upload paths (drag / paste / camera / gallery), full keyboard shortcuts, best-in-class mobile UX, Web Share save-to-Photos, and shareable preset URLs. Everything runs locally in your browser — no uploads, no login, default no ad scripts, no daily limits.