How to make a picture black and white

On an iPhone, open the photo in Photos, tap Edit, tap Filters and choose Mono, Silvertone or Noir. On Android, open it in Google Photos, tap Edit, and either pick one of the black and white filters or drag Saturation all the way down. Both take under a minute and keep your original. The rest of this guide covers every other device — and how to get rich blacks instead of flat gray.

Removing the color is the easy part. Every phone and computer can do it in a few taps. What separates a black and white photo that looks deliberate from one that looks like a mistake is contrast, and that is the part almost every quick answer leaves out. It is covered in full below. Or skip the steps: the free black and white photo converter does it in your browser, with the contrast settings from this guide built in.

The Photos app has three black and white filters and a manual control.

With a filter:

1. Open the photo in Photos and tap Edit. 2. Tap Filters — the icon of three overlapping circles. 3. Swipe to Mono, Silvertone or Noir and tap Done.

Mono is a neutral, even conversion. Silvertone is cooler, with a little more contrast. Noir is the strongest — deep blacks and bright highlights — and is usually the best starting point for a portrait taken in good light. On some older versions of iOS the middle filter was called Tonal rather than Silvertone.

With the manual control, which gives you more say over the result:

1. Tap Edit, then the Adjust icon (a dial). 2. Choose B&W, or set Saturation to −100. 3. Adjust Contrast and Black Point to taste — the contrast section below explains what to aim for.

Nothing is lost: tap Edit, then Revert, and the color original comes back.

To shoot in black and white from the start, choose Mono, Silvertone or Noir from the filters in the Camera app before you take the picture. The filter can be removed later in Photos. Menu labels move between iOS versions; if a name above does not match your phone, the filters are always somewhere under Edit.

The exact names depend on your phone and app version, but every Android phone has two routes.

Google Photos (on most Android phones, and free on iPhone too):

1. Open the photo and tap Edit. 2. In Filters, swipe along the row to the black and white ones. Google renames them between versions — recent and older releases have used names such as Vista, Vogue and Eiffel — so look for the gray thumbnails rather than a particular name. 3. Or go to Adjust and drag Saturation all the way to the left. 4. Tap Save copy to keep the color original alongside the new version.

Samsung Gallery:

1. Open the photo and tap the Edit icon (the pencil). 2. Tap Filters and swipe to one of the grayscale filters. Tap the filter again to set its strength. 3. For black and white with one color left in — a red coat in an otherwise gray picture — use Spot color from the editing tools instead.

Mac (Photos app): open the photo, click Edit, then either Filters (the same Mono, Silvertone and Noir as on iPhone) or Adjust, where the Black & White section has intensity and tone controls.

Windows (Photos app): open the photo, click Edit image, and either choose a black and white filter or reduce saturation to zero in the adjustment controls. Labels differ between Windows versions, but both options sit in the same editor.

If the built-in editor is not enough, these three are free and go further.

Snapseed (iPhone and Android, free). Open the photo, tap Tools, then Black & White. It offers presets such as Neutral, Contrast and Bright, and color filters that change how each color translates to gray — the same idea as the color filters photographers once screwed onto the lens.

Photopea (free, in a web browser, nothing to install). Open the photo, then Image > Adjustments > Black & White. You get a slider for each color — reds, yellows, greens, cyans, blues, magentas — which is the most control any free tool offers.

GIMP (free desktop editor for Windows, Mac and Linux). For a quick conversion, Colors > Desaturate > Desaturate. For control over how each color channel contributes, Colors > Components > Mono Mixer.

A straight conversion often looks flat, and there is a specific reason. Removing color keeps only brightness, and many colors that look completely different have almost the same brightness. A red shirt against green grass is a striking contrast in color and close to nothing in gray. The picture loses its separation and turns to a muddy middle tone.

Both pictures above come from the same photograph. The one on the left is a plain color removal. The one on the right had four things done to it, in this order.

1. Choose which colors become light. This is what a color filter or a channel mixer does. A red or orange filter lightens skin, sand and warm colors and darkens a blue sky and green foliage — flattering for faces, which is why it is the classic choice for portraits. A green filter does the opposite and darkens skin, so leave it for landscapes. In Snapseed this is the color-filter row; in Photopea and GIMP it is the per-color sliders.

2. Set a true black and a true white. Something in the picture — a dark shirt, hair, a deep shadow — should be properly black, and the brightest highlight should be close to white. Use Black Point on an iPhone, the Levels or Blacks control elsewhere. Without this, the whole image sits in gray.

3. Add contrast to the middle tones, gently. A little more contrast gives the picture weight. Too much and faces lose their detail: shadows under the eyes go black and skin highlights burn out.

4. Check the faces at full size. Zoom in. If the eyes have disappeared into shadow or a cheek has gone pure white, pull the contrast back. A black and white portrait succeeds or fails on whether you can still see the person.

Two things to avoid: heavy "clarity" or "structure" sliders, which make skin look gritty, and strong filters like Noir on a dim indoor photo, where they turn digital noise into ugly grain.

Black and white is strongest where light and shape do the work: side light from a window, strong shadows, textured surfaces, and above all expression. It is a natural fit for portraits, because removing color removes everything that dates a photograph — the clothes, the furniture, the tint of the light.

It is weakest where the color is the subject: a sunset, autumn leaves, a bright painted wall. And a dark, grainy photo taken indoors at night rarely improves, because the conversion has no good light to work with. Black and white or color goes into when monochrome is the right choice for a family photo and when it is not.

Everything above changes one thing about a photograph: its color. The background stays where it was — the beach, the car park, the kitchen. The light stays the light that happened to fall that day. The people stay arranged the way they happened to stand.

A studio-style black and white portrait changes those as well. The background becomes a plain dark field with nothing in it but the people. The light becomes directional, falling across the faces the way studio lights are set up to. And the people are arranged on purpose. That is relighting and restaging, not a filter, and no conversion setting will get you there.

You can move some of the way at home: photograph people against a dark wall, well forward of it, lit from a window, and convert using the steps above. Family photos on a phone covers where to stand and when to shoot.

Or start from a photo you already have. Graydrop restages it as a black and white family portrait from a photo — one photo in, one 9:16 monochrome portrait back in about three minutes, $12.99, seen watermarked before you decide whether to buy it. In December there is a Christmas version in which the Santa hats are the only color.

But if you like the photograph as it is and only want it in black and white, the free tools above are the right answer, and they cost nothing.