Grayscale image converter
Create a grayscale PNG using a weighted RGB brightness approximation.
Input
How to use this tool
- Enter your values or choose a local file. Replace the example data with your own.
- Review options, units and assumptions, then run the tool.
- Check the result before copying or downloading it. Keep an original copy of important files.
Method & assumptions
Create a grayscale PNG using a weighted RGB brightness approximation.
gray = 0.2126R + 0.7152G + 0.0722BWorked example
RGB → gray / gris / grau
Limits & important notes
Output depends on your input and browser support. Keep the original. Large files may exceed your device’s memory.
Content updated:
Privacy & Free to use
Are my inputs stored?
Your inputs stay in this tab. We do not receive your files, pasted text or calculation values.
Is this tool free?
Yes. No signup or payment is required.
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