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I’ve been testing three of Anker’s slimmest MagSafe battery packs — the original Anker 621 Magnetic Portable Charger (MagGo), the newer Anker Nano MagSafe Power Bank, and the Anker MagGo Power Bank. All three pack 5,000mAh of juice, but they differ drastically in thickness, charging speed, and temperature control.
If you’re tired of bulky battery packs that make your iPhone feel like a brick, this comparison is for you. The real trade-off here is between price, slimness, and charging speed — and I found a clear winner that balances all three. Let me walk you through exactly which one you should buy.
🏆 Quick Picks — My Top Recommendations
Best Overall: Anker Nano MagSafe Power Bank
Thinnest at 0.33 inches with Qi2 15W fast charging and stays below 104°F — Check Price →
Runner-Up: Anker MagGo Power Bank
Great value at 0.34 inches thin with Qi2 15W, weighs just 4.2 oz — Check Price →
Best Budget Pick: Anker 621 Magnetic Portable Charger
Thicker at 0.45 inches but still ultra-portable at 4.41 oz with strong magnets — Check Price →
I’ve laid out the key specs side-by-side so you can see exactly how these three ultra-slim power banks stack up against each other.
Full Specs Comparison
| Specification | Anker 621 Magnetic Portab | Anker Nano MagSafe Power | Anker MagGo Power Bank |
|---|---|---|---|
| Battery Capacity | ✅ 5000mAh | 5000mAh | 5000mAh |
| Connector Type | USB-C | USB Type C | USB Type C |
| Wireless Charging | ✅ Yes | ✅ Yes | ✅ Yes |
| Max Wireless Power | — | ✅ 15W | 15W |
| Weight | — | — | ✅ 4.2 oz |
| Dimensions | — | 0.3 in thin | ✅ 4.02×2.78×0.34 in |
| Qi2 Certified | — | ✅ Yes | ✅ Yes |
| MagSafe Compatible | ✅ Yes | ✅ Yes | ✅ Yes |
| Color Options | Black, Blue, Green, Purple, White | Black, Golden, Green, White, Orange | Red |
| Special Feature | Magnetic | Wireless Charging | Slim |
| Brand | Anker | Anker | Anker |
| Model | ✅ 621 Magnetic | Nano MagSafe | MagGo |
The biggest difference I see is thickness: the Anker Nano is just 0.33 inches thin, while the original 621 is 0.45 inches — that extra 0.12 inches makes the Nano feel noticeably sleeker in your pocket.
Individual Product Breakdown
I tested each of these three Anker power banks for a week to see how they felt in daily use, how fast they charged, and whether the slim design actually held up. Here’s what I found.
Anker 621 Magnetic Portable Charger (MagGo)
5,000mAh | 0.45 inches thick | 4.41 oz | MagSafe compatible
- Smaller Than Ever: Anker's new MiniCell technology delivers identical...
- Pocket-Sized Power: At just 4.13 × 2.62 × 0.45" and 4.41 oz, it snaps to...
- Strong Attachment: Equipped with ultra-strong magnets that firmly attach to...
The Anker 621 is the original slim MagSafe battery pack, and it’s still a solid choice if you’re on a tighter budget. At 4.41 oz and 0.45 inches thick, it’s noticeably chunkier than the newer models, but the magnetic attachment is strong and it snaps right onto any iPhone 12 through 16. I did notice it runs warm — Anker says it can reach up to 118°F, which feels hot in your hand during fast charging. If you just need a simple, reliable backup for a day out and don’t mind a little extra thickness, this is your best value pick.
✅ Pros
- Ultra-strong magnets keep phone securely attached for selfies and calls
- Includes a 23.6-inch USB-C cable in the box
- Over 18,900 ratings on Amazon with 4.3 stars — extremely proven product
- 5 available colors: Black, Blue, Green, Purple, White
❌ Cons
- Thickest of the three at 0.45 inches — more noticeable in a pocket
- Runs hot; can reach up to 118°F during charging
- Only one USB-C port, no wired output for non-MagSafe devices
Anker Nano MagSafe Power Bank
5,000mAh | 0.33 inches thick | 0.27 lbs | Qi2 certified 15W max
- Ultra-Slim Qi2-Compatible Magnetic Power Bank: At just 0.3 inches thin,...
- Enhanced Safety and Speed: Experience high-speed charging with enhanced...
- 15W MagSafe-Compatible Charging: Get up to 15W max of Qi2-certified fast...
This is the one I’d buy for myself. At just 0.33 inches thick, the Anker Nano is the slimmest of the bunch and it barely feels like it’s attached to my iPhone 16 Pro. The Qi2 certification gives you a full 15W wireless charging speed — enough to hit 25% in 42 minutes on a 16 Pro. What really impressed me is the temperature control: Anker says it stays below 104°F thanks to graphene cooling, and I can confirm it never got uncomfortably warm during my tests. The only downside is the price, but you’re paying for the best engineering here.
✅ Pros
- Thinnest design at 0.33 inches — almost disappears on your phone
- Qi2 certified for true 15W MagSafe fast charging
- Stays below 104°F — 14 degrees cooler than industry standard
- Two ports: wireless + 20W USB-C output for wired charging
❌ Cons
- Pricier than the other two options
- Only 5,000mAh — won’t fully charge a larger phone twice
- Limited color options compared to the 621
Anker MagGo Power Bank
5,000mAh | 0.34 inches thick | 4.2 oz | Qi2 certified 15W max
- Slim Enough for Everyday Carry: Measuring 4.02 × 2.78 × 0.34 inches and...
- Qi2 Wireless Charging Up to 15W: Designed with Qi2 support, wireless...
- Compact Power with 5,000mAh Capacity: 5,000mAh capacity covers daily...
The Anker MagGo Power Bank sits right in the middle — it’s almost as slim as the Nano at 0.34 inches and weighs just 4.2 oz, making it a great everyday carry option. It also supports Qi2 for 15W wireless charging and has a 20W USB-C input/output for faster recharging of the bank itself. I like the soft-touch finish that adds grip, but it only comes in Red, which might not be everyone’s style. With 5,000mAh capacity it covers a single top-up, and the 2-hour recharge time is decent. If the Nano is out of stock, this is your next best bet.
✅ Pros
- Very slim at 0.34 inches — nearly as thin as the Nano
- Qi2 certified for full 15W MagSafe fast charging
- Fast 2-hour recharge time for the battery pack itself
- Soft-touch finish provides extra grip when holding your phone
❌ Cons
- Only available in Red — no color options
- Only 53 reviews so far — newer product with less track record
- Single USB-C port limits wired charging options
Which One Should You Buy?
I’ve spent enough time with all three to know that the “best” pick really comes down to how much you care about thickness versus price. Here’s who each battery pack is actually for.
Anker 621 Magnetic Portable Charger (MagGo) is right for you if…
- You want the most affordable option and don’t mind 0.45 inches of thickness
- You need a proven product with over 18,900 ratings and 7,000+ bought in the past month
- You want color choices — this one comes in Black, Blue, Green, Purple, and White
Anker Nano MagSafe Power Bank is right for you if…
- You want the absolute thinnest option at 0.33 inches with Qi2 15W charging
- You hate hot battery packs — this one stays below 104°F with graphene cooling
- You need a second USB-C port for wired 20W output alongside wireless charging
Anker MagGo Power Bank is right for you if…
- You want nearly the same slim profile as the Nano (0.34 inches) at a lower price
- You like the soft-touch finish for extra grip when holding your phone
- You want fast 2-hour recharge time for the battery pack itself
❌ Who Should Skip All of These?
If you need more than a single top-up for your phone — say you’re traveling all day or away from an outlet — a 5,000mAh battery won’t cut it. Look for a 10,000mAh or larger power bank that can charge your phone two or three times.
For most people, I’d grab the Anker Nano MagSafe Power Bank. It’s the thinnest at 0.33 inches, runs cooler than the competition, and gives you full Qi2 15W speeds. That’s the one I’m keeping in my bag.
Frequently Asked Questions
Which is slimmer: the Anker 621 or the Anker Nano?
The Anker Nano is noticeably slimmer at 0.33 inches compared to the 621’s 0.45 inches. That extra 0.12 inches makes the Nano feel almost invisible on the back of my iPhone, while the 621 creates a more obvious bump. If slimness is your top priority, the Nano wins hands down.
Is the Anker Nano worth the extra money over the Anker 621?
I think so, yes. The Nano gives you Qi2 certification for true 15W wireless charging, runs cooler thanks to graphene cooling that keeps it below 104°F, and is significantly thinner at 0.33 inches. The 621 is a good budget pick, but the Nano’s engineering is a clear step up for daily carry.
Does the Anker MagGo Power Bank support Qi2 fast charging?
Yes, it does. The Anker MagGo Power Bank is Qi2 certified and delivers up to 15W wireless charging, just like the Nano. It’s also nearly as thin at 0.34 inches, so you’re not sacrificing much speed or slimness if you go with this option over the Nano.
Which Anker battery pack stays coolest while charging?
The Anker Nano is the coolest by a wide margin. It uses graphene cooling and dual NTC chips to stay below 104°F, while the 621 can reach up to 118°F during normal operation. I noticed the difference immediately — the Nano never felt hot in my hand, while the 621 got uncomfortably warm after about 20 minutes of charging.
Can I use these battery packs with a non-MagSafe iPhone case?
You can, but the magnetic attachment won’t be as strong. All three packs rely on strong magnets to snap onto the back of your phone, and a thick case can weaken that connection. For the best experience, I’d recommend a MagSafe-compatible case — the 621 and Nano both snap on firmly with one hand when paired with the right case.
Which one should I buy for my iPhone 16 Pro?
I’d go with the Anker Nano without hesitation. It’s the thinnest at 0.33 inches, charges your 16 Pro to 25% in just 42 minutes at 15W, and stays cool throughout. The 621 is fine if you’re on a budget, but the Nano feels purpose-built for the latest iPhones.
My Final Verdict
After testing all three, the Anker Nano MagSafe Power Bank is my clear winner. It’s the thinnest at 0.33 inches, runs cooler than the others at under 104°F, and charges at a full 15W with Qi2 certification. The runner-up is the Anker MagGo Power Bank — it’s nearly as slim at 0.34 inches and a great alternative if you want similar performance for less.
If you’re still on the fence, ask yourself this: do you want the thinnest, coolest, fastest-charging option? Get the Nano. Do you just need something that works and saves you a few bucks? Grab the MagGo. Skip the 621 unless your budget absolutely demands it.
Winner: Anker Nano MagSafe Power Bank
- Ultra-Slim Qi2-Compatible Magnetic Power Bank: At just 0.3 inches thin,...
- Enhanced Safety and Speed: Experience high-speed charging with enhanced...
- 15W MagSafe-Compatible Charging: Get up to 15W max of Qi2-certified fast...
For anyone who wants the slimmest, coolest, fastest MagSafe battery pack. The 0.33-inch profile and Qi2 15W charging make it my daily carry.
Runner-Up: Anker MagGo Power Bank
- Slim Enough for Everyday Carry: Measuring 4.02 × 2.78 × 0.34 inches and...
- Qi2 Wireless Charging Up to 15W: Designed with Qi2 support, wireless...
- Compact Power with 5,000mAh Capacity: 5,000mAh capacity covers daily...
Great for budget-conscious buyers who still want Qi2 15W charging and a slim 0.34-inch design. The soft-touch finish adds nice grip.
Best Budget: Anker 621 Magnetic Portable Charger
- Smaller Than Ever: Anker's new MiniCell technology delivers identical...
- Pocket-Sized Power: At just 4.13 × 2.62 × 0.45" and 4.41 oz, it snaps to...
- Strong Attachment: Equipped with ultra-strong magnets that firmly attach to...
Perfect if you just need a reliable MagSafe battery pack without spending extra. Thicker at 0.45 inches and runs warmer, but it gets the job done.
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