Nitecore NU25 vs NU20 and the Best Backpacking Power Bank
How we did this: we read Nitecore’s own specification pages for its ultralight headlamps and power banks, checked on 29 Sep 2026. Prices are not listed on Nitecore’s pages and change often, so we leave them out. We have not field-tested these products.
Two electronics decide most of an ultralight kit’s power: the headlamp and the power bank. Nitecore’s NU20 Classic and NU25 UL headlamps weigh 38 g and 47 g, and its NB10000 Gen4 power bank 143 g. The number to watch is usable energy: a “10,000 mAh” power bank delivers 6,200 to 7,200 mAh at 5 V, by Nitecore’s own ratings.
Nitecore NU25 vs NU20 vs NU33 headlamps

| Headlamp | Weight (with headband) | Battery | mAh per gram | Max output | Max runtime |
|---|---|---|---|---|---|
| Nitecore NU20 Classic | 38 g (1.34 oz) | 500 mAh | 13.2 | 360 lm | 97 h (1 lm) |
| Nitecore NU25 UL | 47 g (1.66 oz) | 700 mAh | 14.9 | 400 lm | 45 h |
| Nitecore NU33 | 95.5 g (3.37 oz) | 2,000 mAh | 20.9 | 700 lm | 147 h (6 lm) |
Source: Nitecore product pages, checked 29 Sep 2026. All three are USB-C rechargeable and rated IP66. mAh per gram is our calculation.
NU20 Classic for the lightest: 38 g and a 500 mAh battery. NU25 UL for 9 g more: a 700 mAh battery, 400 lumens and three white color temperatures (3,000, 4,500 and 6,500 K), which Nitecore pairs with a red light. NU33 when runtime matters more than weight: 95.5 g, but a 2,000 mAh battery, the most battery per gram of the three.
Check price →Backpacking power bank: Nitecore NB10000 Gen3 vs Gen4
| Spec | NB10000 Gen3 | NB10000 Gen4 |
|---|---|---|
| Weight | 150 g (5.29 oz) | 143 g (5 oz) |
| Capacity (headline) | 10,000 mAh at 3.85 V, 38.5 Wh | 5,000 mAh at 7.8 V, 39 Wh (“equivalent to 10,000 mAh 3.9V”) |
| Rated energy at 5 V | 6,200 mAh (2 A) | 6,800 mAh (3 A); 7,200 mAh (1 A) |
| Max output | 22.5 W, USB-C | 22.5 W, USB-C |
| Water resistance | IPX5 | IPX7 |
Source: Nitecore product pages, checked 29 Sep 2026.
What “10,000 mAh” really gives you

A power bank’s headline capacity is measured at its cells’ voltage, not the 5 V your phone charges at, and conversion loses some energy. Nitecore publishes the usable figure as “rated energy”: 6,200 mAh at 5 V for the Gen3, 62% of its headline, and 7,200 mAh at a gentle 1 A for the Gen4. Plan your charges from the rated figure, not the headline. For the same 10,000 mAh class, the Gen4 is 7 g lighter, gives you more usable energy and is rated IPX7 rather than IPX5.
Check price →Offline navigation apps: FarOut, CalTopo, Gaia GPS
Many hikers navigate with a phone and offline maps, which is one reason the power bank matters. FarOut builds its app around long-distance trail guides for hiking, biking and paddling. CalTopo and Gaia GPS are general topographic mapping apps for planning your own routes. Whichever you use, download the maps before you lose signal and put your phone in airplane mode to save battery.
FAQ
Nitecore NU25 or NU20?
How much does the Nitecore NU25 weigh?
What is the best backpacking power bank?
Why does a 10,000 mAh power bank not give 10,000 mAh?
Which offline map app should I use?
The bottom line
For ultralight electronics, the Nitecore NU20 Classic (38 g) or NU25 UL (47 g) covers lighting, and the NB10000 Gen4 (143 g) covers charging with 6,800 to 7,200 mAh of usable 5 V energy. Size your power bank from the rated energy, not the headline mAh.
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- Ultralight Camp Chair: Helinox Zero vs Nemo Moonlite Elite
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