Grayscale Converter
Convert images to grayscale
Click or drop an image hereChoose an image
About Grayscale Converter
Grayscale Converter removes the color from a picture. The default method weights red, green, and blue the way the eye perceives brightness (Rec. 709, the weights of the CSS grayscale filter), so a blue sky stays darker than green grass. You can also use the older Rec. 601 weights, a plain average, the lightness (brightest plus darkest, halved) or a single channel. A threshold option gives pure black and white, for scans, stamps, and signatures. A PNG or WebP keeps its transparency. The gray values are computed in your browser.
How to convert an image to grayscale
- 1Click the upload box and choose a color picture.
- 2Pick a "Method", or check "Pure black and white (threshold)" and move "Threshold".
- 3Click "Convert to grayscale".
- 4Check the preview and click "Download"; JPG, PNG, and WebP keep their format, and every other format becomes PNG.
Formats and limits
- Methods
- Rec. 709 luma (default), Rec. 601 luma, average, lightness, red, green, or blue channel only
- Threshold
- From 1 to 254, default 128: pixels at or above it turn white, the others black
- Input formats
- JPG, PNG, WebP, GIF, BMP, AVIF, or another picture your browser reads
- Output format
- JPG (quality 92), PNG, or WebP like the original, other formats as PNG; saved with three equal color channels
- Largest image
- Refused above 268 MP
Where your image is processed
The gray values are worked out by this page in your browser and the picture is not uploaded to anyone. The converted file is held in the tab until you download it. The text of a displayed error, cleaned, is reported to us with the tool and your browser's name and version, without your image.
Frequently asked questions
Which method should I use?
Use Rec. 709 luma, the default, for most photos: it applies the weights of the CSS grayscale() filter and keeps blues dark and greens light. Rec. 601 follows older TV and JPG weights. Average and lightness treat the three colors equally, so blues come out lighter.
Can I make pure black and white with no gray?
Yes. Check "Pure black and white (threshold)" and set "Threshold" between 1 and 254: pixels whose gray value reaches it become white, the others black. It suits signatures, stamps, and scanned text.
Is the result a one-channel grayscale file?
No. The pixels become gray, but the file is saved as an ordinary JPG, PNG, or WebP with three equal color channels, which every viewer opens. The transparency of a PNG or WebP is kept.
Tips and tricks
- ✓Try "Red channel only" and "Blue channel only" on the same photo: each click starts from the original, so comparing methods is quick.
- ✓To see the color and gray versions side by side, open both in Compare Images.