Image to Grayscale Converter
Turn photos into grayscale or crisp black and white in one click — choose how colours become greys, fine-tune brightness and contrast, add a sepia tone, and convert as many images as you like.
At a glance
- Converts to shades of grey or pure black and white, with a before-and-after slider to compare.
- Seven ways to turn colour into grey: Luminance (Rec. 709 in linear light, the default), Rec. 601, average, lightness, or a single red, green or blue channel.
- Black and white uses an automatic threshold (Otsu’s method) or your own, with optional Floyd–Steinberg dithering to keep shading in photos.
- Adjust intensity (partly desaturated looks), brightness and contrast, and add a sepia tone.
- Converts many images at once and downloads them as a ZIP — as JPG, PNG or WebP. Neutral grey PNGs are saved as true 8-bit greyscale (1-bit for black and white), so files are much smaller.
- Works with JPG, PNG, WebP and HEIC. Images are processed in your browser and location data is removed.
Step by step
How to convert an image to grayscale
- 1
Add your images
Drop one or more photos on the page, browse for them, or paste with Ctrl+V.
- 2
Choose grey or black & white
Pick Shades of grey or Black & white, and a method if you want a different look.
- 3
Fine-tune
Adjust brightness, contrast and intensity, or add a sepia tone. Drag the slider on the preview to compare.
- 4
Download
Download each image, or Download all (ZIP) — as JPG, PNG or WebP.
Features
Everything you need, nothing you don’t
Natural-looking greys
The default method keeps the brightness you see, so reds and blues don’t turn muddy or washed out.
Crisp black and white
Perfect for scans, signatures and line art — or dither photos for a newspaper-print look.
Batch conversion
Drop a whole folder of photos; every image uses the same settings and downloads together as a ZIP.
Before and after
Drag the slider over the preview to compare the original with the converted image.
Small files
True greyscale PNGs store one value per pixel instead of three, typically far smaller than colour PNGs.
Private
No uploads: conversion happens on your own device, even for large photos.
Which grayscale method should I use?
| Method | Formula | Best for |
|---|---|---|
| Luminance | 0.2126 R + 0.7152 G + 0.0722 B, in linear light | Photos — keeps the brightness people see |
| Rec. 601 | 0.299 R + 0.587 G + 0.114 B | Matching most other apps and older software |
| Average | (R + G + B) ÷ 3 | Quick, simple results |
| Lightness | (max + min) ÷ 2 | A soft, low-contrast look |
| Red channel | R | Dramatic skies and smooth skin, like a red filter on film |
| Green / blue channel | G or B | Foliage detail (green) or a moody, grainy look (blue) |
Grayscale or black and white?
Grayscale keeps up to 256 shades of grey, so a photo still shows every tone — this is what most people mean by a black-and-white photo.
Black and white (1-bit) uses only pure black and pure white. It suits scanned documents, signatures, stamps, logos and line drawings, and makes the smallest files. Turn on dithering to fake grey tones with dots when converting photos.
FAQ
Frequently asked questions
How do I convert a photo to black and white?
Is grayscale the same as black and white?
Are my photos uploaded?
Can I convert several images at once?
Why is the grayscale PNG smaller than the original?
Can I make a sepia photo?
Keep going
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