Most rock chips can be repaired if they are caught early. The working rule is a chip you can cover with a quarter, sitting away from the edge of the glass and out of the driver's line of sight. That rule of thumb is not folklore: the published repair standard puts the limit for a bullseye at one inch, and a quarter is just under an inch across. Once damage reaches the edge, picks up a second crack, or lands in the part of the windshield you look through, replacement is normally the right call.
The longer version is worth two minutes, because size is the part everyone asks about and it is not the part that usually decides it. Shape, location, and age decide more chips than diameter does.
Four things decide it, roughly in this order: how big it is, what shape it is, where it sits, and how long it has been there. Most articles cover the first one. The other three are where the answer actually comes from.
The shapes, and what each one means
Tell us which of these you are looking at and you have told us most of what we need to know.
- Bullseye. A dark circle with a clear cone under it, from a stone hitting square on. These are the classic repairable chip. They fill well and they usually come back close to clear.
- Star break. A small centre with short legs running out from it. Also usually repairable, with one caveat: the legs are what spread. A star break is the one most likely to grow between the day you notice it and the day you get in.
- Combination break. A bullseye with legs. Repairable in most cases, and it is the most common thing we actually see.
- Half moon, or partial bullseye. The same as a bullseye with one side missing. Usually repairable.
- Chip or pit. A piece of the outer layer gone with no crack under it. Often cosmetic and stable, but worth having looked at rather than assumed.
- Long crack. A single line, usually from an impact you never noticed or from an edge stress point. This is the one most likely to be a replacement.
Those are not casual labels. They are the damage types named in the published repair standard, which is the next section.
There is an actual published standard, and almost nobody quotes it
Windshield repair is not a matter of opinion. There is an American National Standard for it, ROLAGS, the Repair of Laminated Automotive Glass Standard, and it sets size limits by damage type:
| Damage type | Repairable up to | |---|---| | Bullseye | 1 inch across | | Half moon | 1 inch across | | Combination break | 2 inch body, not counting the legs | | Star break | 3 inches across | | Crack | 14 inches long |
Two things usually surprise people here.
The quarter rule is real. A US quarter is just under an inch across, which is why "can you cover it with a quarter" has survived as the rule of thumb for a bullseye. It is not folklore, it is the standard expressed in pocket change.
The crack limit is far longer than people expect. Fourteen inches is most of the way across a windshield, and a lot of people replace glass they did not have to. That said, the standard is a ceiling, not a promise. Length is only one of the tests, and a long crack repair is more demanding, more visible afterward, and more likely to keep running than a small bullseye. The type, the location, and the condition of the break decide it together. That is why the answer to this question is a photo and not a tape measure.
Location beats size
Three places on the windshield change the answer regardless of how small the damage is.
The edge. The perimeter of the glass is where the windshield is bonded to the vehicle, and it is carrying load. A crack that reaches the edge has a path to run along and structural work it is no longer doing. The standard draws its hard line here at an edge crack that intersects more than one edge, which is not repairable at all, and shops treat the approach to that line with more caution than the same damage in the middle of the glass.
Your line of sight. Not the passenger's, not the middle of the glass. The standard calls it the Driver's Primary Viewing Area, and it applies tighter limits inside it than anywhere else on the windshield: damage larger than an inch is not repairable there at all, the finished repair cannot leave a pit bigger than 3/16 of an inch, and it cannot sit within 4 inches of another repair.
The reason is honest. A repair fills a break and restores strength, and it usually leaves the spot far less visible than it was, but it does not always vanish. A faint distortion you cannot stop noticing at night is a bad trade in the one part of the glass you cannot avoid looking through. Michigan's obstruction law is written around the same area. Where that line actually sits.
Behind the camera. If your vehicle has a forward-facing camera at the top centre of the windshield, that camera reads the road through the glass. Damage near it is worth mentioning specifically when you call, along with the year, make, and model, so we can tell you what your vehicle needs. More on windshield cameras and recalibration.
The part nobody mentions: how old it is
A chip repair works by cleaning the break out and injecting resin into it under pressure, then curing it hard. The bond is between resin and clean glass.
A break that has been open for months has had rain, road salt, wax, and dirt driven into it. It can still be repaired, and it often is, but the result is less likely to come back clear and the fill has less to grab. A chip repaired in week one is a better repair than the same chip repaired in month six, even though nothing about its size has changed.
That is the real argument for calling early, and it is separate from the argument about spreading.
What each one costs you
A chip repair is one of the cheapest jobs in this shop. One customer wrote that hers was 50 dollars and took 15 minutes, the easiest car repair she had had. Your price depends on the damage and we quote it before we start. A replacement is a different order of number, and on a vehicle with a camera it also includes recalibration afterward. What actually moves that number.
Insurance usually breaks the same way. Many policies cover a repair with little or no deductible, because an insurer would rather pay for a fill today than a windshield in February. A replacement goes through comprehensive coverage subject to your deductible. We help you get the claim set up, and from there we handle it. How Michigan glass coverage works.
Same damage, two months apart, two very different bills.
Michigan is what turns one into the other
Glass expands and contracts with temperature, and a break is a weak point where that movement concentrates. A cold windshield hit with a hot defroster, a warm one hit with cold rain off the lake, a hard pothole on a frost-heaved road in March: those are the events that turn a repairable star break into a crack running to the edge. Every year the same calls come in during the first hard freeze week, about a chip somebody has been driving with since August.
If you have damage right now and it is small, this is the good window. It is clean, it is still a repair, your coverage is more likely to handle it cheaply, and nobody is scheduling around a snowstorm.
What to do about it
Send a photo of the damage, taken from outside the vehicle, close enough to see the shape and far enough back to show where it sits on the glass. That is usually enough for us to tell you which one you are looking at before you drive anywhere.
If it is still a chip, book a windshield chip repair in Holland. If it has already run, book a windshield replacement in Holland.
Call 616-396-3487 or request a quote. We will tell you which it is, and we will not sell you a windshield you do not need.