Image to Grayscale – Convert Photo to Black and White Free
Convert any image to grayscale (black and white) in your browser. Uses accurate luminance formula. JPG, PNG, WebP supported. Download PNG. No upload required.
Drop an image here or click to upload
JPG, PNG, WebP supported
What is Image to Grayscale – Convert Photo to Black & White Free?
An image to grayscale converter removes all color information from an image, leaving only shades of gray from black to white. The tool uses the ITU-R BT.601 luminance formula (Gray = 0.299R + 0.587G + 0.114B) which matches human perception of brightness. This is more accurate than a simple average of the three channels. All processing happens in your browser using the Canvas API.
How to Use Image to Grayscale – Convert Photo to Black & White Free
- 1Upload your image by clicking the drop zone or dragging an image onto it.
- 2The tool converts the image to grayscale instantly using the luminance formula.
- 3Compare the original and grayscale versions side by side.
- 4Click 'Download Grayscale PNG' to save the output.
Key Features
- ✓Accurate ITU-R BT.601 luminance conversion
- ✓Side-by-side before/after preview
- ✓JPG, PNG, and WebP input supported
- ✓PNG output with full quality
- ✓No file upload — processes in your browser
Benefits
- →Create black and white versions of photos
- →Reduce image complexity for printing
- →Prepare images for documents and reports
- →Test UI designs in grayscale for accessibility
Why Use Irreva for Image to Grayscale – Convert Photo to Black & White Free?
Frequently Asked Questions
What grayscale formula is used?
The tool uses the ITU-R BT.601 luminance formula: Gray = 0.299×R + 0.587×G + 0.114×B. This matches human perception of brightness more accurately than a simple average.
What image formats are supported?
JPG, PNG, and WebP images are all supported. The output is always PNG to preserve quality.
Is the original image affected?
No. The conversion creates a new image in your browser. Your original file on disk is unchanged.
Are there any file size limits?
No server-side limits apply — the conversion happens entirely in your browser. Very large images (over 50 MB) may take a few seconds depending on your device.
Is my image uploaded?
No. The image is processed entirely in your browser using the Canvas API. It is never sent to any server.
What formula is used for grayscale conversion?
The ITU-R BT.601 luminance formula: Gray = 0.299 x R + 0.587 x G + 0.114 x B. This weights green heavily because the human eye is most sensitive to green light.
Is my image uploaded to a server?
No. The image is processed entirely in your browser using the Canvas API. Your file never leaves your device.
What format is the output?
The output is always PNG, which is lossless and supports high quality.
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