Black & white
Convert a photo to greyscale — never uploaded.
How it works
Three steps, and nothing leaves your device.
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1
Drop in the photo
Any common format, including iPhone HEIC. Nothing leaves your device.
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2
It converts immediately
Each pixel is replaced by its luminance — no settings to get wrong.
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3
Download the result
A greyscale image at the original dimensions.
Why some greyscale conversions look muddy
- Averaging the three channels is the usual mistake. (R+G+B)/3 treats every channel as equally bright, and they are not. The eye is far more sensitive to green than to blue, so an average makes greenery too dark and skies too light, and the whole picture loses separation.
- This uses Rec. 709 luma. Red counts 21%, green 72%, blue 7% — the weighting used by HDTV and by every serious image tool. Foliage keeps its brightness, blues stay dark, and tones stay apart from one another.
- Greyscale is not the same as desaturating. Desaturation in an editor often works in a different colour space and leaves faint casts behind. This sets all three channels to the same value, so the result is genuinely neutral.
- It does not always shrink the file. A greyscale PNG still stores three channels unless the encoder chooses a greyscale mode. Expect a modest saving at best; if size is the goal, compress the image instead.
Frequently asked questions
Why not just average red, green and blue?
Because the eye does not weight them equally. An average makes green too dark and blue too light — the usual reason a black-and-white conversion looks flat.
Is this the same as removing saturation?
Not exactly. Desaturating can leave slight colour casts depending on the colour space; this sets all three channels to the same luminance value, so the result is strictly neutral.
Will the file get smaller?
Usually only slightly. Use the compressor if size is what you are after.