About Negative
Negative inverts an image the way a photographic negative does. Every pixel has each of its three color channels replaced by 255 minus the value that channel held, so light areas become dark, dark areas become light, and the relationships between the hues inside the frame survive while the whole picture is turned inside out. Black becomes white, white becomes black, and a mid gray stays roughly where it was.
The work happens in a single pass over the pixel buffer. The image is drawn onto a canvas at its own natural size, the pixels are read out once, every four-byte group is inverted channel by channel, and the buffer is written back. Because the canvas matches the source dimensions nothing is scaled and nothing is cropped, and the result is handed over as a PNG whatever format the file arrived in - a JPEG or a WebP source comes back as a PNG with its original compression gone.
The effect has no controls, which is the point of it: there is nothing to tune and nothing to watch while dragging a slider. The only comparison on offer is the input and output previews side by side. Transparency survives untouched, because only the color channels are inverted, so the shape of a transparent PNG is preserved while its colors reverse.
How to use Negative
- 1 Choose an image file with the picker and check the preview that appears.
- 2 Press the calculate button - there are no settings to adjust first.
- 3 Compare the two previews and download the result once it looks right.
- 4 Invert the downloaded PNG again if you need to get back to the original colors.
Frequently asked questions
Does the inversion preserve transparency?
Yes. Only the red, green and blue channels are inverted, so the alpha value of every pixel is written back unchanged and a partly transparent region stays partly transparent.
Can I get the original file back?
Not byte for byte. The pixels are re-encoded as PNG, so a JPEG source loses its original compression along the way. Inverting the downloaded PNG returns the colors to their original values, but not the original file itself.
Is there a strength or channel control?
No. The inversion is total and applies to all three color channels at once, and there is no slider, no way to invert one channel only and no readout of the resulting pixel values.
Why is the download always a PNG?
The result is written out from a canvas in PNG form whatever the input type was, so an uploaded JPEG or WebP is converted on the way out. That keeps the inversion lossless, since PNG does not add compression artefacts of its own.
Free, online, and private
Free to use
Negative is completely free. There is no account to create, no login, and no hidden charge or usage limit.
Runs online in your browser
It is a free online tool that runs entirely in your browser. Nothing to download or install — open the page and start using it right away.
Your data stays private
All processing happens locally on your device. Your input is never uploaded, stored, or tracked, so it never leaves your browser.
How Negative behaves in detail
These are the specifics of this implementation — the exact ranges, defaults and fixed settings you are working with.
| Parameter | Value |
|---|---|
| Input | an image file chosen from the device; the tool has no settings fields, so the effect is applied as soon as the convert button is pressed |
| Operation | every pixel has its red, green and blue values replaced by 255 minus the value that channel currently holds |
| Pass | the image is read into one pixel buffer and written back in a single loop, four bytes per pixel - red, green, blue and alpha |
| Pixel dimensions | the working canvas is created at the natural width and height of the source image, so nothing is scaled and nothing is cropped |
| Result format | the result is re-encoded as PNG whatever the input file was, so a JPEG or a WebP source comes back as a PNG |
| Download name | the file is offered with a png extension and keeps the base name of the image that was uploaded |
Compiled from the implementation of this tool and checked against it by itoolnet.
What Negative does not do
Knowing the edges of a tool saves more time than another list of its features. These are the cases where it will not do what you might expect.
- Transparency is untouched. Only the three color channels are inverted, so the alpha value of every pixel is carried through unchanged - a half-transparent region stays half-transparent instead of becoming its inverse.
- The conversion is destructive. Pixels are rewritten and re-encoded as PNG, so the original JPEG or WebP compression is gone for good, and getting back to the original colors means inverting a second time rather than recovering the file you started from.
- The inversion is fixed and total. There is no strength control, no way to invert one color channel on its own and no readout of the resulting pixel values - the only comparison offered is the input and the output previews shown side by side.
Tested and documented by itoolnet, the team that builds and maintains this site.