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Grayscale Image Converter

Turn a photo black and white, with a slider for how far to go.

Image
Drop an image here or click to browse
or paste from clipboard (Ctrl+V) · JPEG, PNG, WebP
Files stay in your browser. Nothing is uploaded.

How to convert an image to grayscale

  1. Add your image

    Drop a JPG, PNG, or WebP onto the tool, click to browse, or paste one from your clipboard. It converts straight away.

  2. Set the intensity

    The slider starts at 100 percent, fully black and white. Lower values leave some of the original color in for a muted, partly desaturated look.

  3. Download the result

    Click Download image to save the file in the same format it arrived in, at the original pixel dimensions.

Why use this tool

Partial desaturation, not just on or off

The intensity slider blends between the original colors and full gray, so you can land on a muted look rather than being forced all the way to black and white.

Weighted for how eyes work

Brightness is calculated with the standard luminance weighting rather than a flat channel average, so reds and blues do not turn into the same flat middle gray.

Transparency is preserved

PNG and WebP sources keep their alpha channel, so a cutout stays a cutout instead of gaining a white box.

Format and resolution kept

The output matches the format you dropped in and holds the original pixel dimensions, so it drops straight back into wherever the original was used.

Nothing is uploaded

The conversion runs on your device with no account, no queue, and no watermark.

About this tool

Grayscale is the fastest way to make a set of mismatched images look like they belong together: product shots from different suppliers, headshots taken in different rooms, or screenshots pulled from a dozen apps. Removing color also removes the main thing that makes them clash, which is why press kits, documentation, and print layouts lean on it so heavily.

The conversion uses a luminance-weighted formula, meaning green contributes most to the perceived brightness of a pixel, red next, and blue least. A flat average of the three channels is easier to write but produces muddy results, with bright reds and deep blues collapsing to a similar gray. The weighted version keeps a red shirt and a blue sky visibly different in the black and white version.

The intensity slider exists because full desaturation is not always the goal. Around 60 to 80 percent leaves a hint of the original color, which reads as a considered edit rather than a filter. The output keeps whatever format you dropped in, so PNG and WebP files hold their transparency. To adjust the actual pixel size use the image resizer, to flip the tones instead use the invert colors tool, and to shrink the finished file use the image compressor.

Frequently asked questions

How do I make an image black and white?
Drop the image into the box. It is converted to grayscale immediately at full intensity, and you can pull the slider back if you want some color left in.
What does the intensity slider do?
It blends between the original and the fully gray version. At 0 percent nothing changes, at 100 percent the image is entirely black and white, and the values between give a partly desaturated look.
Which formats can I use?
JPG, PNG, and WebP. The result is saved in the same format the image arrived in, so transparency in a PNG or WebP is preserved.
Does the image get smaller or lower resolution?
The pixel dimensions stay the same. Grayscale files often compress a little smaller, and the before and after sizes are shown under the preview.
Are my images uploaded anywhere?
No. Everything happens in your browser and the file is never sent to a server.

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