Grayscale Image Converter
Turn a photo black and white, sepia or inverted, with adjustable strength.
Your original stays as it is; the result is saved as a new file. Saving as JPG compresses it again, so quality can change slightly.
HEIC photos may not open directly in this browser. Convert to JPG first with HEIC → JPG / PNG Converter.
This photo is too large (over 40 million pixels). Please make it smaller first. Crop & Resize Images
Add a photo and the black-and-white version appears next to the original right away. Sepia gives a warm brown, old-photo tone, and Invert flips light and dark. Lower the strength to keep some of the original colour. The photo is processed on this device only.
How to use
- Choose or drop a photo.
- Pick Black & white, Sepia or Invert and set the strength.
- Check the format and press Download.
Examples
A pure red pixel (255, 0, 0)
A pure red pixel (255, 0, 0) becomes grey level 76 at 100% black and white, and (166, 38, 38) at 50%, keeping half its colour. Inverted, the same pixel turns cyan (0, 255, 255).
FAQ
Is my photo uploaded?
No. The photo is changed inside your browser and is never sent or stored anywhere.
How is black and white calculated?
Each pixel's grey level weights red, green and blue by how bright they look to the eye (0.299, 0.587, 0.114). That is why green turns out lighter than blue.
What does strength do?
It blends the original with the effect. 100% is the full effect, 0% is the original, and 50% is halfway.
Does it keep PNG transparency?
Yes. Saved as PNG, transparent areas stay transparent. JPG can't store transparency, so those areas become white.
Can I turn it back into colour?
Not from the result file; the colour information is gone. Your original is untouched, so use that when you need colour.
Can I use a very large photo?
Up to 40 million pixels (width times height). Resize larger photos first. On devices with little memory, smaller photos can still be slow.