Proofing, also called proving, is a step in the preparation of yeast bread and other baked goods in which the dough is allowed to rest and rise a final time before baking). During this time, the dough undergoes further fermentation and takes on its final size and shape. The purpose of proofing is to activate the yeast in the dough, which consumes the sugars and starches in the dough and expels carbon dioxide, causing the dough to expand and become puffy and pillowy.

Proofing is essential in breadmaking because it encourages the yeast to multiply, resulting in a light loaf. The length of rest periods, including proofing, can be determined by time at specific temperatures or by characteristics. Often the "poke method" is used to determine if a dough has risen long enough. If the dough, when poked, springs back immediately, it is underproofed and needs more time. Some breads are considered fully proofed if the indent left by the poke springs back slowly, while others are considered fully proofed when the indent remains and does not spring back).

Overproofing occurs when a fermenting dough has rested too long. Its bubbles have grown so large that they have popped and tunneled, and dough baked at this point would result in a bread with poor structure). To avoid overproofing, it is important to assess the dough periodically and look for some rise in the dough, large bubbles, airiness, and lightness. When the dough is poked, it should feel relaxed.

In summary, proofing is a crucial step in breadmaking that allows the dough to rise and become light and fluffy. It is important to assess the dough periodically to avoid overproofing and ensure that the bread has the desired structure.