Convert any image to black and white (grayscale) entirely in your browser — adjustable brightness and contrast, no server upload.
Also flip images with the Image Flip tool or compress images with the Image Compressor.
This image grayscale converter works as a black and white photo converter, online desaturation tool, and browser-based image editor for photographers, designers, and anyone who needs to remove colour from an image without installing software or uploading files to a third-party service.
Grayscale conversion calculates each pixel's luminance from its RGB values using the perceptual luminance formula: Gray = 0.299R + 0.587G + 0.114B. This formula is not a simple average of the three channels — it weights green most heavily (58.7%) because human eyes are significantly more sensitive to green light than to red (29.9%) or blue (11.4%). Using this weighted formula produces grayscale images that appear natural and balanced, closely matching how the human visual system perceives brightness differences across the spectrum.
A simple average of R, G, and B would produce a technically correct but visually flat grayscale image where, for example, a bright blue sky and a similarly bright green field might look identical despite appearing very different to the eye. The luminance-weighted approach preserves the perceived tonal contrast of the original image. The adjustable brightness and contrast sliders give further control — brightness shifts the overall lightness of the image, while contrast expands or compresses the range between the lightest and darkest pixels, allowing you to create anything from a soft matte look to a high-contrast dramatic black and white effect.
Common use cases include converting colour photographs to black and white for artistic effect, preparing images for print media that requires grayscale, creating consistent visual styles for portfolios or presentations, and reducing cognitive load in UI screenshots by removing distracting colour information. Photographers processing portrait, landscape, and street photography often use grayscale conversion as a starting point for further editing, using the tonal information to guide dodging, burning, and contrast adjustments.