Switching from glasses to contact lenses can be a game-changer when it comes to vision and convenience — but only if they’re worn correctly. One common issue lens wearers face, especially those new to lenses, is putting them in inside out. While not usually dangerous, wearing a lens the wrong way can be uncomfortable and may affect your vision. 

Here’s how to tell if your contact lenses are inside out before putting them in. 

Do the “Taco Test”

The taco test is one of the most reliable tricks. 

How to do it:

• Place the lens between your thumb and forefinger, near the center, so the edges are free. 
• Gently squeeze the lens by pinching it at the edges, like you’re trying to fold it into a taco, being careful not to squish it completely in half. 

If it folds in smoothly like a taco, it’s correctly oriented. If the edges flare outward, it’s inside out.

Check the Shape

Hold the lens on the tip of your finger and look at it from the side. 

• Right-side out: The lens forms a smooth, symmetrical U shape — like a bowl.
  
• Inside out: The edges flare outward, making the lens resemble more of a shallow saucer.

In summary, a perfect half-sphere is correct; a saucer shape is not.

Look for Markings or Tint

Many contact brands include small numbers or letters or a tint near the edge of the lens. The tint is typically blue but sometimes green. 

How to do it:

• Place the contact lens on your fingertip.
• Hold it up to a light and look for a marking or tint.
  

If you can read the numbers and letters correctly, the lens is right-side out, and if they appear backward, it’s inside out. If your lens has a tint, you’ll know it’s right-side out if the edges look bright and inside-out if the edges look pale. 

Note that not all lenses have markings or tint, so don’t rely on this method alone. If you want to know whether your contacts have markings, check the manufacturer’s website. 

Feel the Fit

If you’re still unsure after inserting the lens, your eye will often tell you. 

Signs your contact might be inside out: 

• It feels uncomfortable, gritty, or scratchy. 
• Your vision seems blurry or slightly off. 
• Your eyes water more than usual. 
• The lens moves around more often or doesn’t sit right on your eye.

If you notice any of these signs, remove the lens, rinse it with solution, and try again.

Daily Disposable Contacts

If you wear daily disposable contacts, pay attention to how they sit in the packaging. This will help you remember how they look right-side out and help you put them in correctly every time. It’s highly unlikely that you’ll open the package and find the lenses inside out.

Additional Tips 

Here are a few additional tips for inserting and wearing contacts:

Hand Hygiene — Wash your hands with soap and dry them completely before inserting or removing contact lenses. Avoid oily or heavily scented soaps that can leave residue on your hands and lenses. 

Insertion — Take your time, especially when you’re just starting out, and if in doubt, take your lenses out and recheck. Make sure you blink a few times to help the lenses settle. 

Cleaning and Disinfecting — Clean and disinfect your lenses daily using a fresh solution, and throw them away when they have reached the end of their lifespan. 

Storage — Use a clean contact lens case every day and replace it every three months. Avoid reusing old solution in your case. 

Water Exposure — Avoid swimming, showering, or using hot tubs with your contacts in, as water can introduce harmful bacteria. 

Overwear — You may be tempted to wear your contacts longer than recommended or to sleep in them after a long day, but this can lead to irritation and discomfort and reduce oxygen flow to your eyes. You also risk developing an infection and damaging your cornea. 

Make Sure to Wear Your Contacts Correctly

Being able to tell if your contacts are inside out may take a little practice, but it’s an essential part of comfortable and effective lens wear. By using easy and simple methods like the taco test, checking the lens shape, or looking for brand markings, you can avoid irritation and ensure clear vision all day.

Trust yourself and your eyes — if something feels off, it probably is. By applying these quick checks and tips to your daily routine, you’ll be handling your contacts like a pro in no time.