A 5000mAh power bank can typically charge most smartphones about once, depending on the phone’s battery size and charging efficiency. A phone with a 3,000mAh battery may get around 1 to 1.3 full charges, while a phone with a 4,000–5,000mAh battery will usually get around 60% to 100% charge. In real-world use, some power is lost during charging, so the usable capacity is usually lower than the advertised 5000mAh. Even so, such a portable phone charger is still a convenient option for daily use, commuting, or short trips when you need extra battery on the go.