How long can a baby use a bouncer?

It depends on the model. Newborn-to-6-month bouncers like the Baby Delight Highland have shorter useful windows, while grow-with-me designs such as the Ergobaby Evolve (5.5–25 lbs) and Ingenuity Keep Cozy (up to 40 lbs / 30 months) convert into toddler seats and last considerably longer, which reviewers frequently cite as a value advantage.