Glossary
Windowpane test
A quick check where a piece of dough is stretched thin enough to see light through it, showing the gluten is developed enough.
The windowpane test is a simple way to check whether a dough's gluten has developed enough before moving on to bulk fermentation. A small piece is pinched off and gently stretched outward in all directions with the fingers, watching whether it thins out into a translucent sheet or tears.
A dough that passes will stretch into a thin, slightly cloudy pane you can see light through without ripping, which shows the gluten strands have formed a strong, elastic network able to trap gas during fermentation and baking. A dough that tears quickly or resists stretching altogether usually needs more kneading or more time to rest.
Testing gives a more reliable read than judging by kneading time alone, since flour type, hydration level, and mixing method all change how quickly gluten develops in any given dough. A common mistake is testing straight out of the mixer before the dough has had any rest, which can make even a well developed dough seem to fail the test simply because it has not relaxed yet and springs back too fast to stretch thin.