ENPTES

Threshold a photo without uploading it

Pick a cutoff and download PNG or JPG. Pixels at that brightness or above turn white. The rest turn black. The work runs in this tab.

Runs in your browser Free No sign-up
  1. Choose file
  2. Set options
  3. Get result

Your file never leaves your device. Processed locally in your browser. Nothing is uploaded. Location and camera metadata (EXIF) are removed from the result.

Pixels at the cutoff or above turn white. Darker pixels turn black. Width and height stay the same. PNG keeps transparency. JPG fills empty pixels with white. Camera location is not copied.

How to threshold an image

1. Drop a photo you already have. Audio and video are refused here. 2. Leave 128, or pick 64 or 192. 3. Leave PNG, or pick JPG, then press “Threshold image”.

GustKit reads the brightness of each pixel. At the cutoff or above, the pixel becomes white. Below it, the pixel becomes black. A lower cutoff keeps more of the light areas. A higher cutoff keeps only the brightest pixels. The alpha stays in a PNG. A JPG fills a clear pixel with white first.

One cutoff, two colors

Grayscale image keeps the shades of gray. Posterize image cuts each color channel into a few steps, so a photo can still show several grays. This page keeps only black and white. Duotone maps those shades onto two colors you pick instead.

The photo stays in this tab

The browser canvas does the work. GustKit does not fetch a picture from a link. Camera location is not copied into the download. Close the tab and the file is gone.

How to check the black and white photo

1. Open the original and the download at the same zoom. 2. A bright area should be white. A dark area should be black. 3. If a mid gray disappeared, run again at 64.

Grayscale image keeps the shades. Posterize image keeps a few steps per channel. This page keeps only black and white. Nothing is uploaded.

Frequently asked questions

The download is only black and white and the size did not change. Did it work?

Yes. Threshold replaces every pixel with black or white. Width and height stay the same.

A light gray area turned black. Can I keep it?

Pick 64. That cutoff treats more mid grays as white. 192 keeps only the brightest pixels.

Can I threshold a photo and also posterize it in one step?

No. Threshold it first, or posterize it first, then open the other page on the download.

Is the photo uploaded?

No. The canvas runs in this tab.

The photo is only black and white and the size did not change. Did it work?

Yes. 128 turns mid gray into black or white. Width and height stay the same.

Can I threshold a photo and also add a border in one step?

No. Threshold it first, or add the border first, then open the other page on the download.