We track 26 popular packs and rank them by how much battery you actually get per dollar — the only number that lets a 5,000 mAh MagSafe puck and a 142,500 mAh power station compete fairly. Prices refresh daily.
50,000 mAh of capacity at one of the lowest sticker prices on the chart — the cheapest joule we track today.
Pocketable 18.5 Wh pack at 15 W — fine for a phone top-up, well under the 100 Wh airline cap.
145 W USB-PD output charges a 13″ MacBook at full speed. Just under the airline cap and the cheapest laptop-grade option we track.
| Rank | Power bank | Capacity | Power | Price | Flags | Cost per Wh | |
|---|---|---|---|---|---|---|---|
| 01 |
OHOVIV
OHOVIV Portable Charger 50000mAh Power Bank - 22.5W Fast Charging External Batte
1× USB-C
|
185Wh50,000 mAh | 22.5W | $25.60 | USB-PD |
$0.138 /Wh
cost per watt-hour
|
Buy → |
| 02 |
OHOVIV
OHOVIV Portable Charger Power Bank 50000mAh Battery Pack
1× USB-C
|
185Wh50,000 mAh | 22.5W | $32.42 | USB-PD |
$0.175 /Wh
cost per watt-hour
|
Buy → |
| 03 |
Aaoyun
Aaoyun Portable Charger Power Bank
1× USB-C
|
37Wh10,000 mAh | 22.5W | $12.77 | Carry-onUSB-PD |
$0.345 /Wh
cost per watt-hour
|
Buy → |
| 04 |
UGREEN
UGREEN Nexode Power Bank 20000mAh 45W with Built-in Cable
1× USB-A
|
74Wh20,000 mAh | 45W | $29.32 | Carry-on |
$0.396 /Wh
cost per watt-hour
|
Buy → |
| 05 |
Anker
Anker Power Bank
1× USB-A
|
37Wh10,000 mAh | 15W | $16.39 | Carry-on |
$0.443 /Wh
cost per watt-hour
|
Buy → |
| 06 |
Anker
Anker Zolo Power Bank
1× USB-C
|
74Wh20,000 mAh | 45W | $33.56 | Carry-onUSB-PD |
$0.454 /Wh
cost per watt-hour
|
Buy → |
| 07 |
Miady
Miady 2-Pack Portable Charger
1× USB-A
|
37Wh10,000 mAh | 15W | $17.79 | Carry-on |
$0.481 /Wh
cost per watt-hour
|
Buy → |
| 08 |
GENSROCK
GENSROCK 2 Pack Portable Charger Power Bank 10000mAh
1× USB-C
|
37Wh10,000 mAh | 22.5W | $21.22 | Carry-onUSB-PD |
$0.574 /Wh
cost per watt-hour
|
Buy → |
| 09 |
Belkin
Belkin Portable Charger
1× USB-C
|
74Wh20,000 mAh | 15W | $45.11 | Carry-onUSB-PD |
$0.610 /Wh
cost per watt-hour
|
Buy → |
| 10 |
INIU
INIU 45W Fast Charging Portable Charger
1× USB-C
|
37Wh10,000 mAh | 45W | $23.52 | Carry-onUSB-PD |
$0.636 /Wh
cost per watt-hour
|
Buy → |
| 11 |
UGREEN
UGREEN Power Bank 25
1× USB-C
|
92.5Wh25,000 mAh | 145W | $62.83 | Carry-onUSB-PD |
$0.679 /Wh
cost per watt-hour
|
Buy → |
| 12 |
Jackery
Jackery Portable Power Station Explorer 300
1× USB-A
|
292Wh78,919 mAh | 15W | $202.02 | Power station |
$0.692 /Wh
cost per watt-hour
|
Buy → |
| 13 |
INIU
INIU 20000mAh Laptop Power Bank
1× USB-C
|
74Wh20,000 mAh | 65W | $53.13 | Carry-onUSB-PD |
$0.718 /Wh
cost per watt-hour
|
Buy → |
| 14 |
Anker
Anker Power Bank
1× USB-C
|
74Wh20,000 mAh | 87W | $58.79 | Carry-onUSB-PD |
$0.794 /Wh
cost per watt-hour
|
Buy → |
| 15 |
Charmast
charmast Portable Charger with Built in Cables
1× USB-A
|
37Wh10,000 mAh | 15W | $29.69 | Carry-on |
$0.802 /Wh
cost per watt-hour
|
Buy → |
| 16 |
UGREEN
UGREEN Nexode Power Bank 25000mAh 200W Laptop Portable Charger PD 3.1 Fast Charg
1× USB-C
|
90Wh25,000 mAh | 200W | $73.40 | Carry-onUSB-PD |
$0.816 /Wh
cost per watt-hour
|
Buy → |
| 17 |
Anker
Anker Laptop Power Bank
1× USB-C
|
92.5Wh25,000 mAh | 100W | $79.69 | Carry-onUSB-PD |
$0.862 /Wh
cost per watt-hour
|
Buy → |
| 18 |
INIU
INIU 25000mAh Power Bank
1× USB-C
|
92.5Wh25,000 mAh | 140W | $91.99 | Carry-onUSB-PD |
$0.994 /Wh
cost per watt-hour
|
Buy → |
| 19 |
INIU
INIU Portable Charger
1× USB-C
|
37Wh10,000 mAh | 45W | $36.93 | Carry-onUSB-PD |
$0.998 /Wh
cost per watt-hour
|
Buy → |
| 20 |
Anker
Anker Nano Portable Charger
1× USB-A
|
37Wh10,000 mAh | 45W | $37.04 | Carry-on |
$1.001 /Wh
cost per watt-hour
|
Buy → |
| 21 |
Anker
Anker 621 Magnetic Portable Charger
1× USB-C
|
18.5Wh5,000 mAh | 15W | $22.74 | Carry-onUSB-PD |
$1.229 /Wh
cost per watt-hour
|
Buy → |
| 22 |
Anker
Anker Zolo Magnetic Power Bank
1× USB-C
|
37Wh10,000 mAh | 30W | $46.53 | Carry-onUSB-PD |
$1.258 /Wh
cost per watt-hour
|
Buy → |
| 23 |
Anker
Anker Prime Power Bank
1× USB-A
|
97.1Wh26,250 mAh | 300W | $229.61 | Carry-on |
$2.365 /Wh
cost per watt-hour
|
Buy → |
| 24 |
Anker
Anker MagGo Power Bank
1× USB-C
|
37Wh10,000 mAh | 15W | $90.10 | Carry-onUSB-PD |
$2.435 /Wh
cost per watt-hour
|
Buy → |
| 25 |
Anker
Anker MagGo Power Bank
1× USB-C
|
37Wh10,000 mAh | 15W | $104.54 | Carry-onUSB-PD |
$2.825 /Wh
cost per watt-hour
|
Buy → |
| 26 |
Anker
Anker Nano MagSafe Portable Charger
1× USB-C
|
18.5Wh5,000 mAh | 15W | $81.17 | Carry-onUSB-PD |
$4.388 /Wh
cost per watt-hour
|
Buy → |
One number, no tricks.
Watt-hours measure the actual energy stored — the same unit on your electricity bill. Milliamp-hours, by contrast, only make sense at a stated voltage, which manufacturers shift around to make the headline number look bigger. Watt-hours sidestep the trickery; dividing by retail price gives the true cost of a unit of portable energy.
Prices come from Amazon's official Product Advertising API and refresh once a day. We don't show real-time prices — always click through to confirm before buying. As an Amazon Associate we earn from qualifying purchases. Non-Amazon links may also earn a commission. The ranking itself is deterministic from the formula above and has no human override.
A 20,000 mAh power bank at 3.7 V cell voltage actually holds 74 Wh of energy. A "20,000 mAh" laptop bank at 3.85 V holds about 77 Wh. Marketing copy uses the higher mAh of the internal cells, but you deliver fewer mAh at the 5 V USB output. Watt-hours collapse the confusion into one comparable number.
The TSA and most international airlines allow lithium-ion power banks under 100 Wh in carry-on baggage with no special permission. Between 100 and 160 Wh you need airline approval. Anything above 160 Wh is forbidden on passenger flights — so the Jackery Explorer 300 and Anker 535 power stations can't fly.
Once a day, via the Amazon Product Advertising API. We display the last refreshed price; the checkout price may differ — always click through to confirm before buying.
If you click a Buy link and complete a purchase, we earn a small affiliate commission at no cost to you. Rankings are deterministic from the $/Wh formula and cannot be paid for. We have no incentive to recommend a particular model over another.
We track popular models with verifiable specs. If a power bank you love is missing, email us the manufacturer spec sheet URL and we'll add it.