Types of windshield cracks and chips explained

Knowing what kind of damage you have is the first step before calling a shop — because the type of chip or crack directly affects whether repair is even an option. A bullseye chip and an edge crack may look similar in size, but they have completely different repair paths.

Windshields are laminated safety glass: two thin glass layers bonded around a plastic interlayer (PVB). When a rock or road debris hits, the damage pattern reflects the angle of impact, the speed, and the size of the object. Each pattern has its own name and its own repairability profile. For the full decision framework once you know your damage type, see our repair vs replacement guide.

Rock chip types

Chips are localized impact damage — the rock hit, left a void or crater, and stopped there. Most chips are candidates for resin repair when they meet the size and location thresholds below.

Bullseye chip

A bullseye is a roughly circular crater with a defined outer ring and a darkened impact center. It forms when a rock strikes the glass at close to a perpendicular angle. The shape is clean and self-contained. Bullseye chips under about one inch in diameter are among the most straightforward repairs — the circular geometry makes resin injection reliable and the finished result is typically clean. Larger bullseyes, or those with secondary cracking around the ring, are assessed case by case.

Half-moon chip (partial bullseye)

A half-moon is a semicircular version of a bullseye — the impact point is at the flat edge rather than the center. It usually forms when the rock strikes at a slight angle. Repairability follows the same rule as a full bullseye: under about one inch across, in a location outside the driver's primary sight line and the ADAS zone, most shops can repair it. The partial shape means slightly less resin contact area, but results are generally comparable.

Star break

A star break has cracks or "legs" radiating outward from the impact point, often with a small pit at the center. It forms when a harder or more angular object strikes the glass. Repairability depends on the total diameter across the widest point of the star — shops typically use one inch as the threshold. Legs that cross each other or extend in many directions complicate the resin flow path and may reduce the visual result, even when technically repairable.

Pit

A pit is a small surface void with no visible cracking around it. It is often caused by a smaller piece of debris or a glancing strike. Depth matters more than diameter here: a shallow surface pit on the outer glass layer is almost always repairable. A deep pit that has breached into the PVB interlayer is a replacement call. You can check with a fingernail — if the pit catches firmly and feels like it goes through multiple layers, mention that to the shop.

Combination break

A combination break is exactly what it sounds like — a single impact that produced multiple chip patterns at once (for example, a bullseye with star legs, or a pit surrounded by a partial ring). The name is a catch-all used by shops when the damage does not fit a single clean category. Repairability follows the same one-inch diameter threshold, but the mixed geometry can make resin injection less predictable. Many combination breaks are repairable; some are borderline.

Crack types

Cracks are linear fractures that travel through the glass. Unlike chips, which are localized, cracks extend and tend to spread when temperature changes or road vibration put stress on the glass. Most cracks that have grown past six inches, or that originated at or near the edge, require replacement.

Edge crack

An edge crack starts within about two inches of the windshield's outer perimeter. The glass-to-frame seal creates constant mechanical stress at the edge, and that stress feeds directly into the crack. Edge cracks spread faster than any other crack type — a six-inch edge crack can run the full width of the windshield within a few days in cold weather or after hitting a pothole. Resin repair cannot restore the structural integrity of that edge seal, so replacement is almost always the appropriate course. If you notice a crack starting at the edge, do not wait.

Floater crack

A floater crack starts in the middle of the windshield, away from the edges — typically originating from a chip or small pit that was ignored long enough to propagate. By the time most drivers notice a floater crack, it has often reached six inches or more. Cracks under six inches that started away from the edge and away from the driver's line of sight are sometimes repairable; longer floater cracks generally require replacement. Temperature swing is the main driver of spread, so acting quickly on any visible crack reduces the chance it crosses the repair threshold.

Stress crack

A stress crack appears without any rock impact. There is no chip, no pit, no visible origin point — the crack simply appears in the glass, often running several inches on the first day. Stress cracks are caused by rapid temperature differential: cold glass hit with a hot defroster, or a very hot windshield suddenly cooled by cold water. The thermal shock forces one layer of glass to expand or contract faster than the other. Stress cracks always require replacement — the temperature event that caused them typically compromises the PVB interlayer's adhesion, which resin repair cannot address.

Understanding what kind of damage you have also helps you cut down on future exposure. For practical steps to reduce the likelihood of every crack and chip type covered above, see how to prevent windshield damage. If a KC hailstorm is the cause — where the entire windshield surface takes multiple simultaneous impacts — see hail damage windshield replacement for damage assessment, insurance, and post-storm timing specific to hail events.

Key repairability factors

Regardless of damage type, shops apply the same set of thresholds when deciding whether repair is viable:

• Size. Chips: under about one inch in diameter. Cracks: under about six inches in length (roughly the length of a dollar bill). Damage at or over those thresholds is typically a replacement call.
• Location — driver's line of sight. The area directly in front of the driver (roughly between the 9 and 3 o'clock positions on the steering wheel) is treated as a sight-critical zone. Even a successful repair leaves a small visual artifact. Shops typically recommend replacement for any damage in that zone.
• Location — ADAS camera zone. Many vehicles built after 2018 have a forward-facing camera mounted near the rearview mirror. Damage in or near that zone — even a repaired chip — can affect camera calibration. Replacement is the standard recommendation, followed by a calibration procedure. If your vehicle has driver-assist features (lane-keep, automatic braking, adaptive cruise), confirm with the shop whether your damage is in the camera field.
• Layer penetration. Windshields have three layers. If the damage has reached the inner glass layer, resin cannot bridge the interlayer gap reliably. A shop will assess this during inspection.