Image Error Level Analyser by Jonas Wagner.
From the webpage:
I created a new, better tool to analyze digital images. It’s also free and web based. It features error level analysis, clone detection and more. You should try it right now.
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Image error level analysis is a technique that can help to identify manipulations to compressed (JPEG) images by detecting the distribution of error introduced after resaving the image at a specific compression rate. You can find some more information about this tequnique in my blog post about this experiment and in this presentation by Neal Krawetz which served as the inspiration for this project. He also has a nice tutorial on how to interpret the results. Please do not take the results of this tool to seriously. It’s more of a toy than anything else.
Doug Mahugh pointed me to this resource in response to a post on detecting fake photos.
Now you don’t have to wait for the National Enquirer to post a photo of the current president shaking hands with aliens. With a minimum of effort you can, and people do, flood the Internet with fake photos.
Some fakes you can spot without assistance, Donald Trump being polite for instance, but other images will be more challenging. That’s where tools such as this one will save you the embarrassment of passing on images everyone but you knows are fakes.
Enjoy!