How long do recordable Blu-ray discs actually last?

Recordable Blu-ray discs (BD-R) are often used for long-term file archiving, but their lifespan varies significantly based on how they are made. According to Canadian Conservation Institute data, cheap BD-R discs last an average of five to ten years, while higher-quality discs using silicon and copper alloy or a gold metal layer can last 10 to 20 years. Rewritable BD-RE discs can potentially last between 20 and 50 years. Despite these potential lifespans, discs face threats from physical damage, such as scratches or cracks, and disc rot, which involves oxidation, moisture, mold, and UV exposure. Furthermore, declining industry support for optical drives and discs means hardware to read these formats may become increasingly scarce in the future.