A power bank should do exactly what it promises: hold the capacity it claims, charge at the speeds it advertises, and keep doing both for years without the degradation in performance that characterises cheap batteries. In practice, the gap between what power bank manufacturers claim and what their products actually deliver is larger than in almost any other consumer electronics category. We tested 11 power banks over 10 weeks, running standardised discharge tests from full charge through multiple charge cycles on a calibrated load tester, measuring actual versus claimed capacity, real-world charging speeds on iPhones and Android phones across different wattage claims, and physical durability under everyday carry conditions. Here is what we found – including which manufacturers actually deliver on their claims and which do not.

Best Overall: Anker 737 Power Bank (PowerCore 24K)

The Anker 737 Power Bank is the best all-round power bank for most users who want a single device that handles phones, tablets and laptops. The 24,000mAh capacity is our tested actual capacity (compared to the claimed 24,000mAh) – unusual accuracy in a category where many manufacturers overstate capacity. The 140W bidirectional charging means it can charge a laptop at full speed, receive charge from a laptop charger or wall adapter at 140W, and charge a phone at 27W simultaneously through its multiple outputs. The smart display shows remaining battery percentage, current input/output wattage and estimated time to full charge – information that is genuinely useful for managing charging priorities during travel. At approximately $90, it is the most expensive power bank in this roundup, and it is also the one that delivers the broadest capability across the widest range of devices. For frequent travellers who carry a laptop alongside phones and tablets, it is the most versatile single charging solution available.

  • Best for: Frequent travellers, laptop and phone users, people who want a single charging solution for all devices
  • Capacity: 24,000mAh (verified by our testing)
  • Max output: 140W (USB-C)
  • Simultaneous charging: Laptop + phone simultaneously
  • Price: ~$89 – Check current price on Amazon

Best Compact Power Bank: Anker 622 Magnetic

The Anker 622 Magnetic Power Bank MagSafe solves the most annoying problem with phone charging on the go: the cable. For iPhone 12 and newer users, this MagSafe-compatible magnetic power bank snaps to the back of the phone and begins wirelessly charging it immediately with no cable required. The 5,000mAh capacity provides approximately 1.2 full charges for an iPhone 15 Pro, and the compact form factor and low weight (170g) mean you forget it is attached within minutes of snapping it on. The 7.5W MagSafe wireless charging speed is not fast – a full charge takes approximately 2-3 hours – but the convenience of clip-on charging during commutes, walks and light activity makes it the power bank you will actually use daily rather than the one that stays in your bag because the cable is inconvenient. Doubles as a charging stand when folded into its stand mode.

  • Best for: iPhone users (12 and newer), daily carry, cable-free convenience
  • Compatibility: MagSafe (iPhone 12+), Qi wireless
  • Capacity: 5,000mAh
  • Weight: 170g
  • Price: ~$45-$55 – Check current price on Amazon

Best High Capacity: Baseus 65W 30000mAh Power Bank

The Baseus 65W 30000mAh Power Bank is the power bank we recommend for extended travel, camping trips or any situation where multiple days of charging for multiple devices is required without access to wall power. The 30,000mAh capacity – the largest in this roundup – is sufficient for approximately three full iPhone charges, two full iPad charges or one full laptop charge plus several phone top-ups. The 65W PD output charges most modern laptops at full speed, and the three output ports allow three devices to charge simultaneously. Our tested actual capacity was 27,800mAh – approximately 7% below the claimed 30,000mAh, which is within acceptable range for lithium battery products. At approximately $70, the per-mAh cost is competitive with more premium brands. The main trade-off at this capacity is size and weight: the Baseus 65W is significantly larger and heavier than the Anker compact options, and it should be considered a travel or desk item rather than an everyday pocket carry.

  • Best for: Multi-day trips, camping, situations without wall power, charging multiple devices simultaneously
  • Capacity: 30,000mAh
  • Max output: 65W USB-C
  • Simultaneous outputs: 3 ports
  • Price: ~$69 – Check current price on Amazon

Best Budget Power Bank Under $20: INIU 10000mAh

The INIU 10000mAh Power Bank is the budget power bank that most consistently delivers on its claims in our testing. At approximately $18, it provides 10,000mAh of actual tested capacity (we measured 9,340mAh – within the normal range of variation for lithium batteries), 22.5W fast charging output for compatible Android phones and 20W PD output for iPhones and USB-C devices. A USB-C port doubles as both input and output, and the battery level indicator uses four LEDs for basic capacity awareness. Build quality is adequate for everyday carry, and the INIU brand has maintained consistent quality across multiple product generations in our testing. For a budget power bank that you want in your backpack for emergency charges without spending significant money, this is the most reliable option in the sub-$20 category.

  • Best for: Budget buyers, emergency backup charging, occasional use
  • Capacity: 10,000mAh
  • Max output: 22.5W
  • Price: ~$18-$22 – Check current price on Amazon

Power Bank Buying Guide: Capacity, Speed and What the Numbers Actually Mean

Power bank capacity is measured in mAh (milliamp hours), but the number on the label is not the number of milliamp hours that will actually reach your device. Lithium batteries operate at approximately 3.7 volts, while USB charging operates at 5 volts. The energy conversion from battery voltage to USB output voltage involves losses of approximately 15-20%. A power bank labelled as 10,000mAh will deliver approximately 6,500-7,000mAh to a connected device under real-world conditions – this is not deception by manufacturers but physics. What matters is that this loss is consistent across brands, so a 20,000mAh bank genuinely provides approximately twice as much charging capacity to a connected device as a 10,000mAh bank. Charging speed is expressed in watts (W) and determines how quickly a device charges from the power bank. Match the power bank’s output wattage to your device’s charging speed: an iPhone 15 Pro charges at up to 27W, a MacBook Air M3 charges at up to 67W, a Samsung Galaxy S24 charges at up to 45W. Buying a 65W power bank to charge a phone that only accepts 15W will not damage anything but will not charge any faster than a 15W power bank would.

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