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Make an image black and white

Turn photos into grayscale, pure black and white or sepia, one at a time or 10 in a batch; the conversion runs in your browser and the images stay on your device.

Drop photos to make black and whiteGrayscale, pure black and white or sepia · up to 10 images at once
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Black and white imageの使い方

  1. 1

    Drop the photos

    Add up to 10 colour pictures, or a scanned page, of up to 25 MB each. Grayscale is applied as soon as the first one opens.

  2. 2

    Choose the style

    Keep Grayscale for a classic monochrome photo, pick Black & white for pure ink-and-paper contrast, or Sepia for an old-print tint.

  3. 3

    Tune the tones

    For pure black and white, drag Threshold or press Auto, and switch on Dithering to imitate greys with dots. Adjust adds contrast first if the result looks flat.

  4. 4

    Download

    Save one image, or all of them as a ZIP; the files keep their size and format.

制限と Pro

10 images per batch, 25 MB each, converted at full resolution.

Pro converts up to 500 images per batch, each up to 4 GB. Pro を見る

Black and white image について

Three kinds of "black and white" hide behind one search, and this page makes all three. Grayscale replaces every colour with its brightness, weighting green most and blue least (the 0.299 / 0.587 / 0.114 mix used for television), so skin, sky and foliage keep their natural lightness and the picture reads like a monochrome photograph. Black & white goes further and leaves only two values: each pixel becomes pure black or pure white depending on whether its brightness is above the threshold. That is what you want for a signature, a stamp, a stencil, a laser-engraving file or a scanned form that has to stay legible after heavy compression. Sepia mixes a warm brown tone into the image at the strength you choose, from a faint tint to a full vintage print.

For the two-value mode the Auto button picks the threshold with Otsu's method, which finds the cut that separates the darker and lighter halves of the histogram best. Dithering spreads the rounding error to neighbouring pixels (Floyd–Steinberg), so gradients turn into patterns of dots instead of flat blobs, the look of a newspaper photo or an e-ink screen.

Colour is removed only from the copy you download; the original file isn't touched. Converting cannot be reversed afterwards, so keep the colour version if you may need it. A grayscale JPG is still stored with three channels, so the file size changes little; choose PNG for crisp two-value scans.

プライバシー

The grayscale, threshold and sepia maths runs in a Web Worker in your browser tab, and the new file is encoded on your device. No photo or scan is sent to a server, and nothing about it is logged.

主な機能

Grayscale

Brightness-weighted monochrome that keeps natural tones.

Pure black and white

Two-value output with an automatic or manual threshold and optional dithering.

Sepia

A warm vintage tint from subtle to full strength.

Batch of 10

Same settings for every photo, saved as one ZIP.

Black and white image：よくある質問

What is the difference between grayscale and black and white?
Grayscale keeps up to 256 shades between black and white, so a photo still shows soft shadows and smooth gradients. Pure black and white has only two values, and every pixel is either fully black or fully white. Photographers usually mean grayscale when they say black and white; printers, engravers and document scanners usually need the two-value version.
How do I choose the right threshold for a scanned document?
Press Auto first: it analyses the brightness histogram and places the cut between the paper and the ink. If thin strokes break up, raise the threshold so more pixels count as black; if grey paper turns into speckles, lower it. Turning on Adjust and adding contrast before the conversion also helps with pale pencil or faded photocopies.
What does dithering do?
Dithering imitates grey with patterns of black and white dots. Instead of rounding each pixel on its own, the error is passed to the neighbouring pixels, so a gradient becomes a smooth spread of dots rather than a hard edge. It suits photos printed on one-colour printers, e-ink displays and retro graphics, but it makes text look noisy.
Can I convert several photos to black and white at once?
Yes, up to 10 on the free plan. Every image in the list gets the same style, threshold and sepia strength, and Download all saves them together in a ZIP. Click a thumbnail to check how each picture looks before saving, since a threshold that suits one scan may be too strong for another.
Can I turn a black and white photo back into colour?
No. Once the colour information is removed it is gone, and this page doesn't try to guess colours back with AI. The conversion only affects the file you download, so your original stays as it was on your device. Keep that colour original if you think you may want both versions later.

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