Image Opacity Changer
Choose a picture, fade it, or remove one colour to make it transparent.
Your picture is processed inside this page and never uploaded.
What this tool does
Choose a picture, then either slide the opacity down to fade the whole image, or switch to "Make one colour transparent", click a colour in the picture (a white background, for example) and set the tolerance. The preview uses a checkerboard to show transparency, and the download is a PNG that keeps it.
Scales the alpha value of every pixel, or sets the alpha of pixels close to a chosen colour to zero.
Saves the result as a PNG with transparency.
How to use it
- Choose an image.
- For fading, set the opacity percentage.
- For one colour, pick the colour (click the picture) and set the tolerance and soft edge.
- Press Download PNG.
Why use this tool
Does two jobs on a picture's alpha channel: fade the whole image to any opacity from 0 to 100%, or make one colour (such as a white background) transparent with a tolerance and a soft edge. Watermarks, overlays and logos often need to be semi-transparent, and a white box around a logo needs to disappear. Both come down to the alpha channel, which most simple image tools do not let you edit.
Why we built it
We built the image opacity changer to fade a picture or make one colour transparent, with a checkerboard preview. Remove complex backgrounds with the background remover and add a mark with the image watermark tool.
Who this tool is for
- Designers making watermarks and overlays
- Anyone removing a white background from a logo
- Makers layering pictures
When to use it
- Making a faint watermark or background image.
- Removing a plain white or single-colour background from a logo.
- Preparing a picture to layer on other content.
- Creating a ghosted version of a picture.
How it works
Every pixel has an alpha value from 0 (invisible) to 255 (solid). Fading multiplies each alpha by the opacity percentage. Colour keying measures how far each pixel's colour is from the chosen colour in red-green-blue space; pixels within the tolerance become transparent, and a soft edge fades the alpha across the last part of the tolerance to avoid a hard fringe. PNG stores the alpha channel, so the transparency survives the download.
Example: opacity 50% turns a solid pixel (alpha 255) into one with alpha 128. With the colour set to white and a tolerance of 40, near-white pixels such as (250, 250, 250) become fully transparent.
Colour keying removes that colour everywhere it appears, including inside the subject. For complex backgrounds, use the background remover tool.
What you give it, and what you get back
| Item | Details |
|---|---|
| Image | A JPG, PNG, WebP or other picture your browser can open. |
| Mode and settings | Opacity percentage, or the colour to remove with a tolerance and soft edge. |
| Output | A transparent PNG at the image's size (up to 4,000 pixels on the long edge). |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| White halo around the subject | The tolerance is too low or the soft edge is zero. | Raise the tolerance and add a soft edge. |
| Parts of the subject disappear | They are close to the removed colour. | Lower the tolerance. |
| The download looks opaque | It is a JPEG elsewhere in your workflow. | Keep the PNG, which stores transparency. |
Assumptions and limitations
- One colour at a time.
- The long edge is limited to 4,000 pixels.
Frequently asked questions
How do I make an image transparent?
Lower the opacity to fade the whole picture, or choose "Make one colour transparent" and click the colour to remove.
How do I remove a white background?
Switch to colour removal, click the white area, and adjust the tolerance.
What file type keeps transparency?
PNG. JPEG cannot store transparency.
What does tolerance mean?
How different a colour can be from the chosen one and still become transparent.
Is my picture uploaded?
No. It is processed in your browser.
Is anything sent to a server?
No. Everything runs in your browser and nothing leaves the page.