The Real Reason Your Car Windshield Has Those Small Black Dots

Automobile window detail of black dots
Automobile window detail of black dots

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Every day, you hop in the car for your daily commute. You buckle in, turn on the engine, check the mirrors, and look out your windshield. You've done this hundreds of times before, but today is different. This time, you spot the tiny black dots lining the top of your window. What are those black dots, you ask? Don't worry — they're there for your safety. Here's what you need to know.

What are the little black dots?

"The little black dots on your windshield, including the black band around its perimeter, are called frits," said Richard Reina, a lifelong automotive enthusiast and product training director for CarID.com, a site that sells aftermarket auto parts. According to Reina, the windshield glass in modern cars is bonded to its frame using a strong and long-lasting urethane adhesive.

"This makes the windshield a structural component of the vehicle's body," explained Reina. "The frit is black painted enamel that's baked onto the surface of the glass, and it provides a secure point of contact between the glass, urethane adhesive, and windshield frame."

These frits are also there for aesthetic purposes, placed and baked in a halftone pattern, with smaller dots toward the outside, allowing for a subtle transition to the rest of the glass.

And while they may just appear like a pretty pattern, Craig Campbell, an automotive repair expert and founder and CEO at Auto Parts Guideline, said, "They serve an important purpose and are nothing to worry about. They're there to hold the glass in place and keep it from moving around while the car is in motion. Without these dots, the glass could become loose and eventually fall out of the frame."

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Should you be worried if the black dots have worn off?

According to Campbell, if you notice the black dots are starting to wear off, it's important to have them replaced as soon as possible.

"This is because the adhesive is what keeps the glass in place," said Campbell. "Without it, the glass could become loose and fall out of the frame. While this is unlikely to happen, it's still something that you should be aware of. If you're unsure of how to replace the dots, you can always take your car to a professional for help."

Reina echoed Campbell's thoughts, also noting this isn't a DIY project if you don't know what you're doing. "The windshield's black spots are an important feature, and you shouldn't try to fix or modify them," said Reina. "The frit keeps your windshield bonded to your vehicle, and without it, your windshield would not properly adhere to your car."

When is it time to replace a windshield?

If the black dots have worn off, you may not have to replace your entire windshield. However, there are a few signs indicating it's time for a new piece of glass.

"It's time to replace your windshield if there's a crack in the glass. If the crack is blocking your view, covers more than half of your windshield, or extends to the outside edge, it should be replaced or repaired as soon as you can," said Reina. "If not attended to, cracks are likely to spread and grow."

According to Reina, other signs showing it's time to replace your windshield include pitting, sometimes called sandblasting, which is caused by continued exposure to dust, dirt, and sand, which make small marks on the glass and white haze at the edge (as a result of hail and snow).

Not sure if it's time? That's OK. Campbell added, "If you're unsure whether or not your windshield needs to be replaced, you can always take it to a professional for an inspection."