Convert Image to Grayscale — Black & White Online
0.90
Convert a color photo to grayscale in your browser with Rec.601 luma weights—no upload. Steps: choose an image, apply, download JPEG/WebP/PNG. Example: four-color sample → gray blocks keep relative brightness — files stay on your device.
How it works
Pick a photo, apply grayscale, download. Processing never leaves this tab.
Rules
For each pixel Y=0.299R+0.587G+0.114B; R=G=B=Y; alpha unchanged.
- Rec.601 coefficients match common luma practice.
- Alpha channel is copied unchanged.
- Export re-encodes; JPEG drops alpha.
- Animated GIF: first frame only.
Example
Sample four-color blocks become gray with distinct brightness levels.
Good fits
- Print preview without color ink assumptions.
- Accessibility contrast drafts.
- Stylized black-and-white exports.
Frequently asked questions
Uploaded?
No—everything is local.
Which formula?
Rec.601: 0.299R+0.587G+0.114B.
Can I undo?
Not after download; keep the original file.
Same as CSS filter?
We rewrite pixels, so the saved file is truly grayscale.
Transparent PNG?
Transparency is kept when exporting PNG/WebP.
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Questions or feedback
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