Only glassware specifically made and labeled for oven use should go into an oven. Ordinary, decorative, or previously damaged glass can break from heat or thermal shock even when it feels thick and sturdy.
Look for an oven-safe marking
Check the base, packaging, or manufacturer instructions. Do not assume microwave-safe means oven-safe because the thermal conditions are different.
Avoid sudden temperature changes
Do not move cold glass straight from the refrigerator or freezer into a hot oven unless the manufacturer specifically permits it. Likewise, do not set hot glass on a wet or very cold surface.
Do not use cracked or chipped pieces
A small crack or chipped edge concentrates stress and increases the chance of breakage. Retire damaged ovenware rather than assuming it will survive one more baking cycle.
Follow temperature limits and heat-source restrictions
Some oven-safe glass is not intended for broilers, stovetops, flames, or direct heating-element contact. Follow both the stated temperature limit and the permitted heating method.