Luminosity method (0.299R + 0.587G + 0.114B) is the best for photographs — it matches human visual perception so skies, skin, and foliage appear with natural brightness. Average is useful for technical images. Custom Mix gives full creative control.

Use the Luminosity method and apply the “Dramatic” or “High Contrast” preset. Alternatively, use Custom Mix and increase the Red channel weight to 50–60% — red tones become bright and skies dark, a classic landscape B&W technique.

Grayscale uses 256 shades of gray from pure black to pure white. True black and white (1-bit) has only two values. Our tool converts to grayscale which preserves all tonal detail — it is what is used in professional photography.

Different colors become different shades of gray depending on channel weights. Increasing Red makes red and orange tones brighter. Increasing Blue darkens skin tones and brightens skies. This is how professional B&W film photography worked with colored lens filters.

We support JPG/JPEG, PNG, WebP, and GIF formats up to 10MB. You can convert the output to any format while converting to grayscale.

Completely safe. All processing runs inside your browser using HTML5 Canvas. Nothing is uploaded to any server. Your images stay entirely on your device at all times.