Ebbinghaus Illusion


What you see below is another example of the Ebbinghaus illusion, also known as “same size” phenomenon. Although, in perspective the sphere in the right far end seems larger, in reality both spheres are exactly the same size. We saw exactly the same effect before with our funny nuns. Another example was little more scary – the same size monsters. I like all of them, how about you?

  • Catz

    Wow! I can’t even tell that they are the say size now that I _know_ that! I need a ruler… :)

  • Anonymous

    O.o how are they they same size? The one on the right touches the wall…and has a bigger shadow… unless the space between the walls is smaller at the back, but it doesn’t look like that either…

  • Brummie

    I thought an illusion was when it looks bigger but isn’t? It actually IS bigger.

    • riz

      they are the same size, measure them

  • otowi

    FYI – the Mac Dashboard widget, at least for me, has not updated since the soulwax illusion – and the question mark came back – I had already downloaded the “fix” when the problem first came up….

  • Fred B

    Using the ruler function of the Web Developer Toolbar for Firefox, the front sphere seems to be 10 pixels smaller than the one at the back.

  • Anonymous

    Hey vurdlak my mac widget does not work! I have downloaded the new version, but it just shows a little “?”, however the link still works.

    Just thought i would let you know incase it has happened to anyone else

  • Anonymous

    thats amazing…

  • Kevin

    That’s super cool. I think that this one is by far the best retive sizes ilusions.

  • Anonymous

    … that is because they are not … a simple size test in photoshop clearly shows that the one behind has a larger size … its something like 5 pixels, but still … nice try tho …

  • Anonymous

    try again…bottom 8 % smaller, by measurement.

  • Evandor Bounties

    They aren’t the same size. I just took it into photoshop and the sphere in the back is actually larger.

  • J

    actually they aren’t the same size…I just measured them and the one in the back really is larger…:p

  • Anonymous

    its lying. i measured.

  • Rory

    they aren’t the same size… get a ruler and measure it yourself… the one in the back is atleast 1/8″ bigger…

  • Anonymous

    mac widget doesnt work

  • Frances

    the one that looks bigger IS bigger. i measured them.

  • Anonymous

    how in the world are they the same size?!?! i just don’t see it lol.

  • Mike

    I put a piece of paper on the screen and put marks on the edge of the paper to get the size of the front ball. Then checked it against the back ball. The back ball is BIGGER. Not by much but it is a little bigger.

  • Anonymous


    Well, that’s because they aren’t actually the same size. I just measured, the back sphere is slightly larger. However, it does still appear to be larger than it really is.

  • Ryan

    It still confuses me anyway. Good, but if anon. (comment 19)is telling the truth, it slighty runins the point. Good illusion though!

  • Card Magic Tricks

    no 2nd pic?

  • Anonymous

    This is stupid of cource there the same size but there saying if a person is standing pretty far away from you and you take your fingers and measure his size than hes an inch tall. its an extremely stupid illusion. it would work if they were the same depth

  • Anonymous

    This is one of the best of this kind of illusion I have ever seen. It’s coo how your brain assumes that the walls are paralel.

  • black tiger

    How the hell are they different sizes!!! They are different!!!

  • Anonymous

    wtf? they cant be the same!!!!! the one in the back touches the wall and the front touches!!!!! i dont get it. its cool but makes no sense….

  • I wonder…

    I measured thrice, they’re not the same size!

  • Jared

    ok you have to look at it like they’d be really close. one is somewhat lifting off the ground

  • dibs

    anonymous, the reason they are the same size is probably cuz one end is closed in and the other isnt. and the angle they shot the pic at made them look diffrent sizes.

  • joe

    The rear ball is in fact larger, I mesured it

  • Karbelina

    it’s not the same size…it IS larger…

  • Kei

    The balls in 2D is appearing same size but if you think it in 3D it is actually Different size.


    Yes, as about a billion people have pointed out, the ball in the background really is larger than the one in the foreground. Whoever created this “illusion” is an asshole.

  • Robby

    Yea, the one in the back is def bigger. I measured it too…..kinda lame.

  • RaiderRow

    The ball behind is definitely bigger, I just measured them. However, the illusion still works because the perceived size difference is much larger.

  • baster

    they are not the same, i cut them out in paint and the one behind was larger :P

  • Don

    They are not the same size, I measured in photoshop and the one to the rear is significantly larger. This site is worthless.

  • ray

    guys all of you who are saying the back one is bigger are [email protected]. take away the background using photoshop and only keep the spheres.. they are the same size

    • YoGabbaGabba

      Just tilt your head sidewys to the left

  • YoGabbaGabba

    Srry Diagonal sideways

  • Awesome I

    It’s all about the angle. I once stood in one of those, and I was taller than my older brother! It’s all relevant to the size around the balls.

  • Adrian

    It IS bigger.

  • Kaitlyn

    In the picture they are the same size but in reality they are not.

  • Taylor

    im pretty sure they are reversed though. the bigger looking one should be in the foreground and the smaller looking one in the background

  • Professor

    It’s bigger wtf you guys talking about this is a illusion.I measured it on screen the big one is still bigger.In real life its still bigger because on is fking touching the wall and one is not.

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