Is tempered glass bulletproof?

No, tempered glass is not bulletproof. While tempered glass is much stronger than regular (annealed) glass—approximately four to five times stronger—it is not designed to stop a bullet. Tempered glass is engineered for safety, not high-level security. When it is hit by a high-velocity projectile like a bullet, it will shatter completely and instantly into small, granular pieces. Because of its internal tension, once the surface is breached at any point, the entire pane loses its structural integrity and falls away. This makes it very easy for an intruder to enter a building after the glass has been shot. For a window to be bulletproof, it must be made of multiple layers of glass and plastic interlayers that can absorb the kinetic energy of the round without the entire system failing. While tempered glass is often used as one of the layers in a bullet-resistant 'sandwich,' on its own, it offers almost no protection against firearms. If you need ballistic protection, you must use specifically rated bullet-resistant glazing rather than standard tempered safety glass.