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Monochrome Converter

Free online tool to convert images to monochrome (black and white) directly in your browser. Adjust contrast and brightness. No installation or upload required — your images never leave your device.

Upload an image, adjust contrast and brightness, and export as monochrome. All processing happens entirely in your browser with no server uploads.

1. Upload Image

2. Adjust Settings

3. Export

Preview

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How to Use

  1. 1

    Upload an image

    Click the "Select Image" area and choose an image file (JPEG, PNG, WebP, etc.) that you want to convert to monochrome.

  2. 2

    Adjust contrast and brightness

    Move the contrast slider (-100 to 100) to adjust the difference between light and dark areas. Move the brightness slider (-100 to 100) to make the image lighter or darker. The preview updates in real time.

  3. 3

    Download the image

    Click "Download Image" to save the monochrome result to your device.

Frequently Asked Questions

Are my images uploaded to a server?
No. All image processing happens entirely in your browser. Your images are never sent to any server, ensuring complete privacy.
What image formats are supported?
Any image format supported by your browser can be loaded, including JPEG, PNG, WebP, GIF, BMP, and SVG. The output is saved in the same format as the uploaded file.
Does it work on mobile devices?
Yes. The tool features a responsive design and works on smartphones and tablets through the browser.
How does the monochrome conversion work?
The tool converts images to grayscale using the NTSC weighted average method (0.299×R + 0.587×G + 0.114×B), then applies contrast and brightness adjustments to the grayscale values.