Black/White & Monochrome
This free black & white and monochrome tool converts any image to grayscale, a hard black-and-white threshold, or a Floyd–Steinberg dithered look. Drop or paste an image, pick a mode, and preview the result instantly — all on your device, so nothing is ever uploaded.
Luminance desaturation.
How to use Black/White & Monochrome
- 1 Drop an image onto the box, click to browse, or paste one with Ctrl/Cmd+V.
- 2 Choose a mode: Grayscale, Black & White, or Dithered B/W.
- 3 For Black & White, drag the threshold slider to control how much becomes black vs white.
- 4 The preview updates live — download the finished PNG when you're happy.
Frequently asked questions
Is my image uploaded to a server?
No. All conversion is done in your browser on a canvas, so the image never leaves your device — safe for private or sensitive photos.
What's the difference between the three modes?
Grayscale desaturates using luminance, Black & White applies a hard threshold to pure black or white, and Dithered B/W uses Floyd–Steinberg dithering to fake smoother tone from just two colors.
What does the threshold slider do?
In Black & White mode it sets the cutoff (0–255): pixels brighter than the threshold become white and darker ones become black, so you can tune how light or dark the result looks.
Does the monochrome tool work offline?
Yes. PDFPowerHub is a PWA, so once the page has loaded once it keeps working with no internet connection.