Quick Answer
The only Anker spec that can get you turned away
You get to the gate, the agent glances at your bag, and the question is never “how many milliamp-hours is that?” It’s watt-hours: the number the TSA and FAA actually regulate, printed somewhere on the case in small grey text. Under 100Wh you walk on with no paperwork. Between 101 and 160Wh you need the airline’s approval in advance, and you’re limited to two. Above 160Wh the bank is banned from passenger aircraft entirely, approval or not.
Here’s what makes Anker’s lineup confusing: the numbers on the box are mAh and watts, and neither is the number being checked. A 200W bank sounds bigger than a 250W bank sounds bigger than a 30W one, but output wattage says how fast a bank charges your stuff, not how much energy it stores. Watt-hours come from capacity: roughly mAh ÷ 1000 × 3.6–3.7V for lithium-ion cells. That’s why a 10,000mAh bank is printed around 36–37Wh, and why Anker’s biggest travel bank lands on the oddly precise 99.54Wh: engineered to sit a hair under the ceiling on purpose.
So this page sorts five Anker banks by watt-hours first, then by what they can actually charge. If you want other brands in the mix, our best travel power banks roundup covers INIU and Baseus alongside these. If you’ve already decided you’re buying Anker, stay here: the watt-hour column below answers the question in about forty seconds.
The smallest Anker bank worth travelling with: 10,000mAh (~36–37Wh) with a retractable USB-C cable in the body plus a spare USB-A port. For the traveler who wants a charger in a jacket pocket, not a daypack. The catch is 30W: fine for a phone, far too slow to keep a laptop alive.
Check price on Amazon Live price on AmazonDouble the Nano’s capacity at ~72–74Wh, still comfortably under the 100Wh no-approval ceiling, with 87W across two USB-C and one USB-A and up to 65W to a single device. The one most travelers should buy. The catch is bulk. This is a daypack item, not a pocket one.
Check price on Amazon Live price on AmazonAnker rates this one at exactly 99.54Wh: engineered to sit just under the FAA/TSA 100Wh line, so it’s the biggest bank you can carry on with no airline approval. 250W total, up to 140W to a laptop, with a live wattage display. The catch is size, weight, and gate staff who may want to read the label.
Check price on Amazon Live price on AmazonA 0.58-inch-thin 10,000mAh (~36–37Wh) slab that snaps magnetically onto a MagSafe-compatible iPhone, with a 30W wired USB-C port alongside the 15W Qi2 pad. For iPhone travelers who hate dangling cables. The catch: 15W wireless is half the speed of its own wired port, and Android users get the cable only.
Check price on Amazon Live price on AmazonThe laptop specialist: ~72–74Wh in a 20,000mAh pack pushing 200W across three ports, with a per-port wattage display and a 100W recharge input Anker rates at about 1 hour 15 minutes to full. The catch is that it stores no more energy than the cheaper 87W bank. You’re paying for output, not extra charges.
Check price on Amazon Live price on AmazonAnker power banks at a glance: watt-hours first
The left-hand number is the one that decides whether you board with it. Everything else is preference.
| Anker power bank | Watt-hours (the airline number) | Capacity | Max output | Built-in cable | Best for |
|---|---|---|---|---|---|
| Anker Nano 10,000mAh | ~36–37Wh ✅ | 10,000mAh | 30W | Yes, USB-C | Lightest everyday carry |
| Anker 20,000mAh 87W Our pick | ~72–74Wh ✅ | 20,000mAh | 87W | Yes, USB-C | Capacity plus laptop-capable speed |
| Anker Prime 27,650mAh 250W | 99.54Wh ✅ (Anker-printed) | 27,650mAh | 250W | No, separate cable | Max legal capacity, no approval |
| Anker MagGo Slim 10,000mAh | ~36–37Wh ✅ | 10,000mAh | 30W wired / 15W wireless | No, cable included | MagSafe/Qi2 magnetic charging |
| Anker Prime 20,000mAh 200W | ~72–74Wh ✅ | 20,000mAh | 200W | No, separate cable | Charging a laptop on the go |
Verdict: Buy the Anker 20,000mAh 87W unless you run a laptop all day (Prime 20,000mAh 200W) or want the largest legal brick you can board with (Prime 27,650mAh, 99.54Wh).
Pick by what you charge
- Phone only, and you want to forget it’s there → Anker Nano 10,000mAh (~36–37Wh). Two-ish full phone charges, cable attached, nowhere near any threshold.
- iPhone only, and you hate cables → Anker MagGo Slim 10,000mAh (~36–37Wh). Same energy, magnetic instead of plugged in.
- Phone plus a tablet, or two people sharing → Anker 20,000mAh 87W (~72–74Wh). Three ports, 65W to one device.
- Laptop, working days, back-to-back flights → Anker Prime 20,000mAh 200W (~72–74Wh) for output, or Anker Prime 27,650mAh (99.54Wh) if you’d rather have the energy than the smaller pack.
- Maximum legal capacity, full stop → Anker Prime 27,650mAh. Nothing bigger boards without airline approval.
Anker 20,000mAh 87W: the default answer
This is the one to buy if you don’t want to think about it. 20,000mAh works out to roughly 72–74Wh, which isn’t just legal. It’s legal with a wide enough margin that nobody at a gate is going to squint at it. And 87W across two USB-C ports and a USB-A, with up to 65W available to a single device, is the point where a power bank stops being a phone accessory and starts being able to hold a laptop’s charge steady during a long connection.
The detail that wins it, though, is the USB-C cable built into the body, rated by Anker for 10,000+ bends. The cable you’d otherwise leave coiled on a hotel nightstand is physically attached to the thing you’re carrying. It charges a phone and a MacBook simultaneously off different ports, which on a travel day is the actual use case. You and your laptop, both at 20%, one bank.
- ~72–74Wh, comfortably under the 100Wh no-approval ceiling
- Built-in USB-C cable you can't leave behind
- 87W across 3 ports, up to 65W to a single device
- Charges a phone and a laptop at the same time
- Double the Nano's capacity for a fraction of the Prime's bulk
- Noticeably heavier and thicker than a 10,000mAh bank, daypack, not jacket pocket
- 87W is real but still short of the Prime models for a power-hungry laptop
- No wattage display, so you're reading LEDs rather than numbers
Who should ignore it: anyone whose bag has to stay pocket-sized (buy the Nano or MagGo instead), and anyone who genuinely runs a laptop off battery for full working days: 87W keeps a laptop topped up, but the Prime models are what you want if the laptop is the point.
Anker Prime 27,650mAh 250W: the biggest bank that still boards
99.54Wh. Anker prints that figure in its own listings, and the precision is the whole story: the FAA/TSA no-approval limit is 100Wh, so this bank was designed to land just under it. There is no meaningfully larger power bank you can take through a gate without ringing your airline first and being told you’re capped at two units.
The capacity buys real headroom: 250W combined across two USB-C and one USB-A, with up to 140W sustained to a laptop while a tablet and a phone charge from the other two ports. Anker rates a 16-inch MacBook Pro at roughly 50% in about 28 minutes, and it takes 100W back in on recharge. The Smart Digital Display showing live wattage sounds like a gimmick until you’re rationing power across a delayed travel day and want to know exactly what’s left.
The catch is twofold. It’s the largest and heaviest bank here by some margin, and because it sits right at the edge of the rule, gate staff occasionally want to see the printed Wh rating for themselves. Screenshot the spec page before you fly and the conversation lasts ten seconds.
Anker Prime 20,000mAh 200W: the laptop specialist
Same energy as the 87W bank (~72–74Wh), roughly two and a half times the output. That’s the trade in one line. 200W across three ports with a per-port wattage readout, a 100W recharge input that Anker says refills the whole bank in about 1 hour 15 minutes, and enough punch to take an iPhone 16 Pro to 30% in 15 minutes.
Buy it if your bottleneck is speed: hotel-room turnarounds, a laptop you need usable before boarding, a 90-minute layover that has to refill everything. Do not buy it expecting more charges: at 20,000mAh it stores exactly what the cheaper 87W bank stores, and you’re paying the Prime premium for wattage and the display, not for a longer day away from an outlet. If your trips are more about hours away from a socket than minutes to full, the 27,650mAh Prime is the better spend.
The two pocket banks: Nano vs MagGo
Both are 10,000mAh, both land around 36–37Wh, and both are so far below the airline ceiling that watt-hours stop being a consideration at all. The difference is how they attach to your phone.
The Anker Nano 10,000mAh (model A1259) has a retractable USB-C cable in the body plus a separate USB-A port, 30W in and 30W out, and about 1.97 full charges for an iPhone 15 Pro. It’s the cheapest way to never be at 4% again, and it’s the bank you’ll actually carry because it doesn’t feel like carrying anything.
The Anker MagGo Slim 10,000mAh trades the built-in cable for magnets: Qi2-certified, it snaps flat onto MagSafe-compatible iPhones (12-series and newer) at 0.58 inches thick, with a 30W wired USB-C port and a USB-C cable in the box. Honest limits: the magnetic pad caps at 15W, half the speed of its own wired port, and the magnetic attachment does nothing for Android phones. You’d be buying a slim 30W wired bank with a feature you can’t use. Pair either one with a compact wall plug from our best Anker chargers for travel guide and a universal travel adapter so you can refill them anywhere.
The watt-hour rules, plainly
Three thresholds and one habit. Up to 100Wh: carry on, no approval, no conversation. That covers all five banks here. 101–160Wh: airline approval required in advance, maximum two per passenger. Over 160Wh: banned from passenger aircraft entirely. And the habit: power banks and spare lithium batteries go in carry-on baggage only, never checked, at any capacity.
To check any bank yourself: Wh = mAh ÷ 1000 × 3.6–3.7 (the cell’s nominal voltage). That’s why 10,000mAh prints as ~36–37Wh rather than a round number, why 20,000mAh lands at ~72–74Wh, and why 27,650mAh gets to 99.54Wh. Keep the two specs separate in your head: output wattage (30W, 87W, 200W, 250W) is charging speed, watt-hours is stored energy, and only the second one is regulated.
One last practical note: some banks lack an obvious visible certification sticker, and airlines can still ask to confirm the printed rating at the gate. Keep a photo of the spec sheet on your phone. It costs nothing and it’s the difference between boarding and arguing. For the rest of the kit worth packing around it, see the travel gear hub .
Frequently Asked Questions
Which Anker power bank is best for travel?
For most travelers, the Anker 20,000mAh 87W Power Bank hits the best balance: roughly 72-74Wh (well under the 100Wh airline limit), a built-in USB-C cable, and enough output to meaningfully charge a laptop, not just a phone. If you want maximum legal capacity, the Anker Prime 27,650mAh (99.54Wh) is the largest bank you can carry on without airline approval.
How many watt-hours can a power bank have to bring on a plane?
The TSA and FAA allow power banks up to 100 watt-hours (Wh) in carry-on baggage with no airline approval needed. Banks between 101-160Wh require airline approval in advance and are limited to two per passenger, and anything over 160Wh is banned from passenger aircraft entirely.
Is a 20,000mAh Anker power bank allowed on a plane?
Yes. A 20,000mAh lithium-ion power bank works out to roughly 72-74 watt-hours using the standard mAh-to-Wh conversion, which is comfortably under the FAA/TSA 100Wh no-approval ceiling. It must still travel in carry-on luggage, not checked baggage.
What’s the difference between the Anker Prime 27,650mAh and Anker Prime 20,000mAh power banks?
The 27,650mAh Prime bank (99.54Wh) has more total capacity and 250W combined output, sustaining up to 140W to a laptop while also charging a tablet and phone. The 20,000mAh Prime bank has less capacity (~72-74Wh) but a higher 200W rating aimed at fast laptop charging with a smaller, lighter pack.
Does the Anker MagGo magnetic power bank charge as fast as a wired Anker power bank?
No. The Anker MagGo Slim 10,000mAh caps its magnetic Qi2 wireless charging at 15W, slower than the 30W its own wired USB-C port delivers, and slower than the 87W or 200W output of Anker’s larger wired-only banks. Use the wired port when charging speed matters most.
Do all Anker power banks come with a built-in cable?
No. The Anker Nano 10,000mAh and Anker 20,000mAh 87W both have a built-in USB-C cable, but the larger Anker Prime 27,650mAh, Anker Prime 20,000mAh 200W, and the MagGo magnetic bank ship with a separate cable instead. Check the listing before assuming a cable is attached.
The bottom line
Buy the Anker 20,000mAh 87W unless you have a specific reason not to: it’s the ~72–74Wh sweet spot, the cable is attached, and it charges a phone and a laptop at once. Drop to the Nano 10,000mAh or the magnetic MagGo Slim if pocketability beats capacity, step up to the Prime 20,000mAh 200W for raw charging speed, or take the Prime 27,650mAh at 99.54Wh if you want the biggest bank that still boards without asking permission. Whichever you pick, keep it in your carry-on and know its watt-hour number: tap any card above for the current price.