1. True
2. False

The light blue folder is bigger than the black folder. However the black folder can look bigger due to the color.

1. True
2. False

Square A and B are the exact same shade of gray. However, the brightness of the area immediately surrounding each square changes our color perception of the square.

1. True
2. False

With a skinny pencil and a chunky pen, the width can change the perception of the respective sizes. The pen and pencil are the exact same size.

1. True
2. False

No measuring needed. The horse on the right is smaller than the horse on the left.

1. True
2. False

Use your finger to measure both lines, you'll see they are the same length. Our perception of distance affects our perception of length.

1. True
2. False

Did you "barely" get this one? These two bears are the exact same size.

1. True
2. False

The one on the right is larger. Words have connotations that can stimulate our perceptions in a negative or positive manner.

1. True
2. False

Although the vertical line looks longer, if you measure, you will see that both lines are the same size.

1. True
2. False

If you wanted to get the most chocolate for your buck, buy the candy bar on the left. It's bigger.

1. True
2. False

The horizontal lines look slanted due to the vertical lines not lining up perfectly. Another optical illusion.

1. True
2. False

Whether the arrow heads are normal or inverted changes your perception as to whether the line is longer or shorter.

1. True
2. False

This is the Mueller-Lyer Illusion, which gives the impression that the line is longer when the arrow is pointing outward.

1. True
2. False

Contrast in brightness changes our perception of the size of the object. In this example all the interior rectangles are the exact same size.

1. True
2. False

Location, location, location. If you're going to sell these two houses, you'll get more money for the house on the right as it's bigger.

1. True
2. False

Fashionably priced, these hats would cost the same because they are the exact same size.

1. True
2. False

The three little pigs are the same. The middle pig just appears smaller because its siblings are blocking the sides.

1. True
2. False

Perception of size depends on context. If you compare the center dots only (without any other dots around) you'll notice they are the same size as each other.

1. True
2. False

The Zöllner illusion is a classic optical illusion where a pattern surrounding parallel lines creates the illusion that the lines are not parallel.

1. True
2. False

The interconnection may make them seem like they're the same size, but the right one is bigger.

1. True
2. False

The Hering Illusion shows how when the radial blue lines are present, the red lines appear to be bowed outward, when they are actually straight.

1. True
2. False

The car in front is slightly smaller than the car in back.

1. True
2. False

No matter how big or how small puppies are, they are enormous fun! The one on the right is bigger.

1. True
2. False

If you're getting your first cup of coffee in the morning, your brain isn't in gear yet to note subtle differences. The coffee mugs are the same size.

1. True
2. False

This is called the Moon Illusion where the moon appears bigger when on the horizon. Measure the moons, they are the same size.

1. True
2. False

The Epstein (1965) Familiar Size Experiment, showed how familiar objects come with their own pre-conditioned sizes. That means when a dime is as big as a quarter, we believe it is the closer than the quarter.

1. True
2. False

Plates that are empty versus plates that are full can look like they are different sizes, but these two plates are the same size.

1. True
2. False

We all compare laptops, whether we want a bigger or smaller screen, so this one may be easier for you to answer correctly.

1. True
2. False

Your eyes are tricking you. This is called a Watercolor illusion. Most people experience a faint yellow coloration in the area within the large rectangle, but not within the smaller rectangles. However, the color of the space inside all shapes is white.

1. True
2. False

This is the Leaning Tower illusion. The tower on the right seems to lean more, so it is surprising that these are actually two identical pictures of the tower side by side!

1. True
2. False

The elephants do look different in size due to the perspective. However, they are actually the same size.

1. True
2. False

The black line is connected to the red line. The Poggendorff Illusion shows how a simple line image appears distorted by other aspects of the image such as background and foreground lines or shapes.

1. True
2. False

Kanizsa Triangle is experienced by most people as a solid triangle pointing upward that is lighter and covers an inverted triangle pointing downward, and a set of black discs. However, it is actually a symmetrical figure consisting of three discs each missing a triangular section, and three pairs of lines.

1. True
2. False

So that's where all the missing socks from the dryer went! They aren't the same size so they could never be a matched pair.