Here are four free ways to compare two seemingly identical images.
If you have two identical images and want to compare the visual differences, see four different methods you can use to visualize the differences.
All of this may remind you of fun exercises in a crossword puzzle, but there are times when you will need to be aware of the differences. Especially those who deal with photography or manage a website.
The first three ways to compare are through free web applications, which means you can work from a browser no matter what operating system you are running, Windows or Linux.
The fourth method is a free application that only runs on Windows 10/11. Let's take a look at them:
Table of Contents
1. Diffchecker
The Diffchecker is an online tool that allows you to visually compare two images. In addition to images, you can also use it to compare text files, PDF documents, Excel files and folders. It provides you with a free service and a premium.
Using the free service we are interested in here, you can upload two images through its website and compare them to find out the differences between them.
The process is very simple, upload the first image on the left and the second image on the right. You can use the drag and drop method to upload.
When you upload the second photo the comparison is done automatically. You can use the available tools to find the differences, to see them side by side, or with fade or slider.
Finally you can see the basic differences between files and metadata, such as dimensions, resolution, file size, file type, vertical resolution, latitude, longitude and other image information.
2. Online-Image-Comparison
Try it Online-Image-Comparison which is a very good online image comparison tool. Allows you to compare pixel by pixel images. You can simply upload the two images in the corresponding sections and then compare them.
Drag and drop works here too. After uploading you need to specify the color of highlighting the differences between the two images and then press the Compare key.
It also has the Fuzz option, where it is essentially specifying the pixel size to be compared. If you select a higher value, it means that only the large differences between the two images will be highlighted. And, if you choose a lower value, it will display even the infinitesimal differences.
See in the picture above how this also found the marking "iguru.gr" that we had done in the second photo.
3. TheImageKit
TheImageKit is another free website that offers many image editing tools. One of its many tools is image comparison, which allows you to compare and see the differences between two images. It is very easy to use and you can also download the difference.
And here you can drag and drop and in fact you can take both photos together and drop it with one motion. Otherwise you upload one first and then the other. The comparison is done automatically and the differences appear immediately, without you doing anything.
The application will edit the images and show their differences in pink. The same pieces between the two images will appear in black and white. You can download the image that shows the difference.
4.WinMerge
WinMerge is a free, open source software for Windows 11/10. Also available as a portable version, from PortableApps.com. It's the right software if you do not want to upload your photos online.
Allows you to compare text-based documents, CSV / TSV tables, binaries, and images. You can also compare folders and view and analyze differences between them. Its website speaks Greek, but so does the program, if you additionally install the corresponding translation file.
The good thing is that it allows you to compare three images at a time. You can open three identical images and visualize the differences between them in side-by-side windows.
Its use is simple here as well. Launch WinMerge and click File> New> Image. Go to File> Open and select two or three images you want to compare. Click the Compare button to see the differences between the images.
The program is clearly more detailed than previous web applications, as it gives you the right to customize the various base block size, alpha block, CD Threshold, overlay, etc. It also allows you to zoom in / out the image and enlarge a portion of both images and visualize the difference.
There are some good options in the Image menu, with which you can adjust the comparisons, such as Input / Delete Detection, Information Color Difference, etc.
WinMerge is a great software for comparing documents, images and folders for Windows 11/10. It even lets you compare as well as merge differences between files. You can find some plugins and additional tools (Plugins), such as Generate Patch, Generate Report, Unpacker, etc.