How to Identify the Production Date of Automotive Glass?
3 Answers
Methods to identify the production date of automotive glass: There is a code in the lower left or lower right corner of the car glass. The last or second-to-last row contains a number and several small black dots. The number of small black dots indicates the production month of the glass. If the small black dots are in front of the number, subtract the number of dots from 7; if the small black dots are behind the number, subtract the number of dots from 13. The result is the production month of the glass. Automotive glass mainly falls into three categories: laminated glass, tempered glass, and zone-tempered glass. Laminated glass is a glass product made by bonding two or more layers of glass with one or more layers of transparent adhesive material.
I've been driving for decades and have accumulated a lot of experience in reading the date on car glass. Usually, you can find a string of codes in the corner of the windshield or side window, consisting of dots and small numbers. The dots represent the month, with 1 dot for January and 12 dots for December; the numbers represent the year, for example, ·5· means 2025. By combining the number of dots and the position of the numbers, you can determine the exact date. For instance, dots above the number indicate the first half of the year. This method is simple and practical, especially when buying a used car to help verify the car's age and avoid safety hazards caused by expired glass. If the dots or numbers are blurred or there are other symbols, it might be due to brand differences or damage, and it's worth confirming at a professional shop. I still remember the first time I taught my son to read this—he found it super interesting, and now checking the vehicle has become a family habit.
Finding the production date of car glass is actually quite simple and straightforward. Check the small transparent markings on the edge of the window: dots represent months, with 1-12 dots corresponding to each month, while numbers indicate the year abbreviation, such as '3' standing for 2023. The positional relationship is crucial—dots on the left usually indicate the first half of the year, and on the right, the second half. This helps quickly determine whether the glass is new or old, influencing your decision when buying a car or replacing glass. I usually watch videos to learn these tips, applying them during daily car inspections for convenience and speed, and avoiding scams. If the codes are hard to read, just use a magnifying glass or your phone's flashlight. Fellow car enthusiasts find this method practical, as it helps reduce the risk of accidents.
