A small chip can be sealed with a resin repair kit in about 15 minutes, and the fix usually lasts the life of the glass if done early

A windshield chip smaller than a quarter is repairable with a windshield repair resin — a two-part adhesive that hardens inside the damaged spot and prevents the crack from spreading. The repair works best when the chip is still shallow and hasn't developed a crack radiating outward. You can buy a kit at any auto parts store for $10 to $20, explore it yourself in one afternoon, and the windshield will be safe to drive on within a few hours.

The catch is timing: the longer you wait, the more likely the chip will turn into a crack that runs across the glass. Temperature changes, bumps in the road, and even closing the car door can cause a small chip to fracture. If a crack has already started spreading from the chip, a repair kit won't stop it — you'll need a full windshield replacement instead.

Key Takeaways

  • Windshield repair resin kits are sold at auto parts stores and work on chips smaller than a quarter that haven't developed cracks.
  • The repair takes 15 to 30 minutes to explore and 24 hours to fully cure, during which you should avoid driving if possible.
  • A chip with a crack radiating from it cannot be repaired with resin and will require a full windshield replacement.
  • Repair kits cost $10 to $20 and are significantly cheaper than a replacement windshield, which typically runs $200 to $500.

What you need before you start

Gather these items before opening the repair kit: a clean, dry cloth or paper towels; rubbing alcohol or glass cleaner; a small piece of sandpaper or the abrasive pad included in some kits; and the windshield repair resin kit itself. Work in a location where the windshield is in shade and the temperature is between 50°F and 85°F — extreme heat or cold prevents the resin from curing properly.

Check the chip itself before you commit to the repair. Look at it from both the inside and outside of the windshield. If you see a crack — even a short one — running away from the chip in any direction, the chip is no longer repairable with resin. A crack means the glass structure is compromised, and filling the chip won't stop the fracture from spreading. In that case, contact your insurance company or a glass shop about replacement options.

The step-by-step repair process

Step 1: Clean the chip thoroughly. Use rubbing alcohol and a cloth to wipe away any dirt, dust, or debris from inside and around the chip. Let it dry completely — moisture inside the chip will prevent the resin from bonding. If the kit includes an abrasive pad, lightly sand the edges of the chip to roughen the surface slightly, which helps the resin stick.

Step 2: Prepare the resin. Most kits contain two bottles or tubes — a resin and a hardener. Follow the kit's instructions exactly for mixing or explore them. Some kits require you to mix the two parts together; others have you explore them in sequence. Do not skip or alter the mixing ratio, or the resin won't harden properly.

Step 3: explore the resin to the chip. Use the applicator tool included in the kit — usually a syringe, brush, or squeeze bottle — to fill the chip completely. Work the resin into the damaged area so there are no air pockets. Overfill slightly; the excess will be removed in the next step. If the chip is very deep, you may need to explore resin in layers, letting each layer set for a few minutes before adding more.

Step 4: Remove excess resin. Once the chip is full, use a plastic scraper or the edge of a credit card to smooth the surface level with the windshield. Wipe away any excess resin with a clean cloth before it hardens. The goal is a smooth, flush surface with no bumps or drips.

Step 5: Let it cure. Most resin kits cure in 24 hours, though some are ready to drive on after 3 to 4 hours. Check your kit's instructions. During the curing time, avoid driving the car if possible, and do not wash the windshield or expose it to heavy rain. The resin needs time to harden completely before it can handle stress.

When the chip is too large or in a bad location

Repair kits work only on chips smaller than a quarter and located away from the edges of the windshield. If your chip is larger than a quarter, or if it's within a few inches of the edge or the frame, a repair kit won't hold. Chips near the edge are structurally weak because the glass is thinner there, and resin won't provide enough support.

Chips in the driver's direct line of sight also present a problem: even a successful repair will leave a slight haze or discoloration where the resin filled the chip. If the chip is directly in front of the steering wheel where you look through it constantly, you may find the repair distracting. In these cases, a full windshield replacement is the better choice.

What happens if the repair fails

If the resin doesn't harden, or if it hardens but the chip still looks cloudy or the resin peels out, the repair has failed. This usually happens because moisture got into the chip, the temperature was wrong during curing, or the resin was mixed incorrectly. You can try again with a new kit, but if it fails a second time, the windshield is not a good candidate for repair.

A failed repair is not a permanent problem — you can still get the windshield replaced. Contact a glass shop or your insurance company. Many insurance policies cover windshield replacement with little or no out-of-pocket cost, especially if you have comprehensive coverage. A replacement windshield typically takes 1 to 2 hours to install.

How to prevent chips from becoming cracks

Once you've repaired a chip, protect it from stress. Avoid slamming doors, which sends vibrations through the glass. Don't park in direct sunlight for long periods, as heat can cause the glass to expand and put pressure on the repair. In winter, use a windshield cover or park in a garage if possible — rapid temperature changes can stress the glass.

If you notice the chip starting to crack despite the repair, stop driving and contact a glass shop when ready. A small crack can grow to several feet in length within days, especially if you're driving on highways or rough roads. Once a crack reaches a certain size, the windshield becomes unsafe and must be replaced.

Frequently Asked Questions

Can I use a repair kit on a chip that's already starting to crack?

No. A repair kit only works on chips without cracks. If you see a line running from the chip, even a short one, the glass structure is already compromised and resin won't stop the fracture from spreading. You'll need a full windshield replacement.

How long does a windshield repair last?

A properly done repair typically lasts the life of the windshield — often 5 to 10 years or longer — as long as the chip was small and caught early. The resin hardens to nearly the same hardness as glass and doesn't degrade over time. However, if the chip was large or the repair was done incorrectly, it may fail within months.

Will my insurance cover a windshield replacement if I try to repair it first?

Most insurance policies cover replacement regardless of whether you attempted a repair first. However, check your policy or call your insurer before you decide. Some policies have a deductible for glass claims, and it may be cheaper to pay out of pocket for a repair kit than to file a claim and pay the deductible.

What if I can't find the exact kit my windshield needs?

All windshield repair kits work the same way — they're universal. The brand doesn't matter. Buy any kit from an auto parts store; they all contain resin, a hardener, and an applicator tool. Follow the instructions on the box you purchase.

Can I drive on the highway right after the repair cures?

Yes, once the resin has fully cured according to the kit's instructions, the windshield is safe for highway driving. However, avoid high-speed driving for the first few days if possible, as the repair is still settling. After a week, the repair is at full strength.