Power banks deals
A power bank's printed capacity is never what your phone actually receives, so a little arithmetic upfront prevents disappointment on the road. Live power-bank deals are below, alongside what the mAh number on the box really means.
What to check before buying power banks
- Expect roughly 60–70% of the printed mAh to reach your device once conversion losses are counted.
- A phone battery is typically 4,000–5,000 mAh, so a 10,000 mAh bank gives about one and a half full charges.
- For laptops or tablets, look for USB-C Power Delivery and check the output watts match what your device asks for.
- Airlines generally allow banks up to 100 Wh in carry-on baggage only — roughly 27,000 mAh at 3.7 V — and never in checked luggage.
- Pass-through charging (charging the bank while it charges your phone) is convenient, but not every model does it cleanly.
Common mistake: Ignoring the input side — a large-capacity bank that only charges at 10 W takes the best part of a day to refill.
Frequently asked questions
Why does my power bank charge my phone fewer times than its mAh rating suggests?
Voltage conversion between the bank's cells and your device's charging port wastes roughly 30–40% of the stated capacity — this is normal and applies to every brand.
Can I take a power bank on a plane?
In carry-on baggage only, and generally up to 100 Wh (about 27,000 mAh) without airline approval; always check your specific airline's rule before flying.
Does fast charging wear out a power bank faster?
Heat is the main factor in cell wear, so consistently fast-charging a warm bank in a hot car or bag shortens its usable life faster than slower charging in a cool spot.