Optical illusions come in many forms, from horses and tigers to moving shapes and floating ships. They're a fascinating demonstration of how our brain perceives images based on elements like colour, light and surroundings. Optical illusions have been around for centuries and in many different cultures, delighting and confusing people in equal measure, and social media loves them too, with many optical illusions going viral as they baffle millions of people.
We've picked out some of our favourite optical illusions of each kind in our round-up of must-see optical illusions below. We've included some classics from the past and some new creations too, all to leave you bewildered and amazed. If you're left wanting more, check out these optical illusions that blew our minds, or if you want to have a go at creating your own illusion, make sure you have a look at our guide on how to download Photoshop so you have the tools to make your own digital designs.
01. The expanding black hole optical illusion
Optical illusions are always pretty mind-blowing, but not many come close to this one that can show you the future - well almost. Viewers who stare into the centre of the black hole will instantly begin to see it expanding towards them, but in fact, the image is not moving at all. In actuality, it's just the viewer's brain firing back what it thinks is happening and predicting what we'll see. According to a report in the Frontiers in Human Neuroscience journal, over 86% of people who look at the illusion see the shape expanding. Are you one of them?
02. The hypnotic circle optical illusion
Created by Brusspup, the first optical illusion in our list is a bit of a geometric trick. The white circles appear to form a circular shape that rolls around the inside of the circumference of the red circle. But of course, this is an optical illusion so that couldn't actually be the case. The white circles are actually all moving in a straight lines, the timing just happens to create the illusion that they're moving in a circle. See the full video if you don't believe us!
03. The spinning vortex optical illusion
One type of optical illusion that we can't get enough of are those that appear to be moving but they're actually still images. These are examples of what are known as physiological optical illusions – they're caused by the over stimulation of the brain’s senses as a result fo the eye seeing too much colour, light, movement or dimensions to be able to process.
With its purple and yellow vortex-like design, this one's hypnotic, but we promise it's not a gif or a video. It's a completely still image. What happens is that the combination of the different patterns, light and levels tricks your mind into thinking it's moving when you let your eyes wander over the design. Concentrate on the very centre of the image and you should be able to see it stop.
04. The rotating horse optical illusion
The rotating horse optical illusion has us all asking, which way is it turning? The geometric equine kind of looks as though it snakes around, and many users on TikTok have theorised about the direction of the horse, but we still have no idea which way it turns.
05. Van Gogh Starry Night optical illusion
We're seeing stars with this trippy Van Gogh optical illusion. By staring at the rotating image above, the famous illustration will come to life in a flurry of swirls and movement. It's a great example of how our brains will twist an image based on how our eyes adjust to what they're seeing, and I could stare it for hours. Considering the original painter was a well-known addict to anise-flavoured spirit absinthe, maybe this is exactly how he envisioned the original painting.
06. How many horses are there?
Another equine-themed illusion, this one has been confusing viewers since the 1970s. The design begs the question, how many horses are in the painting? And despite how many times we counted the horses, we never got the answer that the artist, Bev Doolittle, revealed as correct. This is an optical illusion of a different kind. It's what's known as a literal optical illusion since it was created intentionally by the artist to hide or disguise things in plain view, without relying on our minds to trick us. We love them all the same.
07. The cat on the stairs optical illusion
This feline-themed optical illusion has divided the internet. It seems as though no one can decide whether the cat is walking up or down the stairs in this post. While the illusion has been doing the rounds online since 2015, we're still none the wiser about the direction of the cat. See our pick of the best animal optical illusions for more animal-oriented treats.
08. The hidden tiger optical illusion
From small cats to big cats. This is another clever illustrated optical illusion from an artist. Can you spot the hidden tiger in the picture? No, not the first tiger you see, the one that's showing us its teeth. The hidden tiger. We promise it's there lurking there in the image, and you'll kick yourself when you see it. This one is also a literal optical illusion, but one with an amusing cognitive element that made us smile.
09. The impossible slide optical illusion
If you're a really big fan of optical illusions, how about one that you can 3D print? That's exactly what Struck Duck did with this mindbender. In this optical illusion, a ball that appears to roll UP the 3D printed slide, defying gravity. But if you watch the full video, you'll see the illusion depends on the angle that you view it at.
10. The Phantom Queen optical illusion
This mind-boggling video features the 2021 winner of the Illusion of the Year contest. The Phantom Queen optical illusion sees the reflection of an invisible queen piece on a chessboard. The video pans round to reveal a clever 3D shape that aligns with the pattern of the chessboard. Hidden under that shape is the Queen, making it look as though she wasn't even on the board.
11. Moving pictures
This mystical moving optical illusion was created by artist Akiyoshi Kitaoka. The design uses the 'anomalous motion phenomenon' to make it look as though it's moving when in reality its a totally static image. Our brain tricks us into thinking the photo is moving because of how the image hits our retinas at a particular location.
12. What's hiding amongst the stripes?
Next up on our list of optical illusions is this eye-crossing striped affair, shared by Dr Michelle Dickinson on Twitter. It springs into life when you shake your head vigorously from side to side (carefully!). An image will start to appear amongst the lines. Which type of furry friend do you see appearing?
13. Spinning discs optical illusion
This is an illusion, featured in Clive Gifford's book Eye Benders, and inspired by experimental psychologist Akiyoshi Kitaoka. No, like the first optical illusion we saw in our list, this is not a GIF but a still image – though the wheels appear to turn in front of your eyes. This happens because of how your eyes process an image, scanning it repeatedly while autofocusing and adjusting. Like in the previous example, there's a way to make it stop – try focusing on one single wheel.
14. How many numbers optical illusion
This number-themed illusion had the internet utterly stumped as it asked the question, how many numbers for you see? At first glance, it looks as though there are only three numbers, but the closer and harder you stare, the more numbers start to appear. There are seven numbers in total, but what numbers are they exactly?
15. Floating ship optical illusion
Most optical illusions seem to be handmade or digital creations, but every now and again an example appears out in the wild – and these incredible 'floating' ships might just be the most mind-boggling phenomenon we've seen. A walker was stunned to see a boat hovering above the water in Cornwall, and a photo of his discovery quickly went viral. This is one of what is a whole sub-genre of optical illusions – accidental optical illusions.
16. The union flag optical illusion
Ever wondered what colour-blind people can actually see? #OnThisDay in 1985, Horizon had the answer via the London Underground map, while viewers stared at a dot to make the Union flag appear in red, white and blue on a blank screen. pic.twitter.com/b1cyJscgzTJanuary 7, 2021
Observing the world in all its colourful glory is something many of us take for granted. But how different do things look if you're colour blind? In a video created by the BBC back in 1985, an optical illusion featuring the Union flag was created to educate people on how colour blindness works.
Viewers are asked to stare at the dot for 20 seconds, after which the screen goes white and, due to a "three receptor phenomena" the flag will appear in its original red, white and blue colours. This, as the narrator explains, is due to said phenomena forcing other colour receptors to take over when some "start to tire". Despite the illusion first being shown over 35 years old, it's still completely mind-boggling. Still celebrating Jubilee Day? Make sure you also see the Queen Elizabeth II optical illusion!
17. Rotating boxes
ついに立体的に動いて見える錯視が完成しました。キューブが回転して見えますね？止まっています pic.twitter.com/nyyWdr5O1EFebruary 14, 2020
These boxes are clearly spinning on the spot, right? Nope! They are, in fact, totally still, with the illusion caused by the flashing background. Focusing on one of the cube's corners stops the spin so you can prove to yourself what is actually happening. Shared by Twitter user @jagarikin, you can find out more about this illusion here.
18. The 2-in-1 spinning optical illusion
This hypnotic optical illusion actually has two mind-bogglers in one. Depending on where you look at the design, the dots will either appear to change colour or completely vanish. Simply follow the light grey spot around or stare at the cross in the centre for 30 seconds to experience the design's multiple illusions. This one, created by Lenstore, made it to our pick of the best optical illusions we've seen this year.
19. What colour is the circle?
Created by the same people behind the optical illusion above, this optical illusion employs a similar concept, but is no less fun to look at despite its simplicity. The circle appears to change colour as it moves from left to right on a gradient background. But it doesn't. The circle actually stays the same colour, all that's changed is the colour of the background that you're seeing it against. This is because the brain perceives colour differently depending on what is surrounding an object. We love an optical illusion with a scientific explanation and that gives us something to bear in mind when using colour in design.
20. The world's oldest optical illusion?
People have marvelled at the joy of optical illusions for a long time, but just how long? This piece of sculpture at Airavatesvara Temple in Tamil Nadu, India, is a contender for the oldest optical illusion around. Among the stunning 12th-century Dravidian architecture and carved ornamentations of chariots and avatars, there appear to be two conjoined creatures with a single head. Focus on the creature on the right, and you should see an elephant, while if you cover the body and legs of the elephant, the animal on the left is clearly a bull.
21. Super Illusion Brothers
スーパー錯視ブラザーズ pic.twitter.com/bLkFhBOCeUNovember 20, 2020
This mesmerising optical illusion will melt your brain. Dubbed 'Super Illusion Brothers', it depicts a bunch of figures walking up the steps and jumping off the top. Doesn't it? You won't be surprised to hear (this is an optical illusion post, after all) that, no it doesn't. Those little green people are actually completely static. This is a ‘bright phi' illusion, which plays with our brain's perception of bright objects.
According to Stanford University (as spotted by 7News), this is a "basic effect" whereby "If a bright point appears at one position, and then reappears at a position shifted to the right, we tend to see a single object moving left to right." Good to know.
If you've been loving these optical illusions and want to see more, check out Muller's puzzling magic eye optical illusion. Or if you'd like to have a go at creating your own, check out our roundup of the best Adobe Creative Cloud discounts, or just scroll down to check out some of the latest deals.