OutIn Nano 2 review
OutIn Nano 2 Portable Espresso Machine
By Tom Calder
A hand-sized espresso maker that heats its own water from a battery, so a power outage doesn't stop your morning coffee and there's no gas or flame involved. OutIn's own lab figures give up to nine cups per charge from room-temperature water, each 50 ml heated to 199°F, and it recharges over USB-C from a power bank or a power station. It makes one small cup at a time, so it's a comfort item, not a way to boil water for a household: a camp stove used outdoors does that for far less. Ground coffee or Nespresso Original Line-compatible capsules both work.
- Best for
- A real espresso in a power outage with no outlet, no gas and no flame
- Skip it if
- You need hot water for the whole household
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Researched, not used. We haven't used this product. This review is built from the maker's specifications, owner reports and our own sizing.
What we like
- Heats its own water: no gas and no flame
- Recharges over USB-C from a power bank or power station
- Ground coffee or Nespresso Original Line-compatible capsules
Worth knowing
- One small cup at a time (85 ml tank)
- Heating and cups-per-charge figures are OutIn's own lab tests
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Our review
OutIn's Nano 2 is a hand-sized electric espresso maker with a built-in battery and heater, so it brews without a flame or an outlet. This researched review covers OutIn's lab-based cup counts, how it recharges, what it will not do with water safety, and where it sits next to the first-generation Nano.
What it is and who it suits
OutIn describes the Nano 2 as a compact, cordless espresso maker, roughly 2.8 inches across and 9.3 inches tall (71 by 236 millimeters) and about 1.6 pounds (740 grams). It has an 85 milliliter stainless steel water tank, a 21-bar pump, a 120-watt heater and a basket for 8 grams of ground coffee. It also takes Nespresso Original Line capsules, but not Dolce Gusto ones.
It suits someone who wants a hot espresso during an outage, a camping trip or a commute, with no gas, no flame and no kettle. It is a comfort item that makes one small cup at a time. This review is researched, not tested. It relies on OutIn's product page and FAQ.
Cups per charge, in OutIn's words
OutIn says a full charge gives up to 9 cups when heating 50 milliliters of room-temperature water from 77°F to 199°F, and over 600 extractions when the water is already hot. It says the heater can warm room-temperature water in as little as 159 seconds. The maker bases every figure on internal OutIn lab testing and says results vary with conditions.
The battery is a 5,000 mAh, 3S pack rated at 54 watt-hours. Dividing by 9 gives about 6 watt-hours a cup, which is our arithmetic, not OutIn's. The practical lesson is the one OutIn's own split suggests: heating cold water is the expensive part, so starting with hot water from a flask stretches a charge far more.
Charging and use
The Nano 2 charges over USB-C. OutIn says 45 W USB-C PD charging takes about 100 minutes and a five-minute charge gives up to 30 extractions with preheated water. It recommends a 20 V, 2.25 A (45 W) adapter and warns that older 5 W phone chargers may charge it very slowly or not at all, and that a USB-A to USB-C cable generally will not give full speed. That matters in an outage: use a power bank or power station with a 45 W USB-C port. Our power station versus generator guide explains what to expect from one.
OutIn says not to brew while charging, because that can trigger over-temperature protection. Only water belongs in the tank, never milk. Clean the outside with a damp cloth, and do not immerse the body or rinse it with boiling water.
Water safety is on you
EPA says to use only properly disinfected water for drinking, cooking and making any prepared drink, and that a rolling boil of at least one minute is its boiling method. OutIn says the machine heats 50 milliliters to 199°F in its test, but does not describe it as a boiler or a water treatment device. If your tap is under a boil advisory, put already-boiled or bottled water in the tank. See our boil water advisory guide and make water safe guide.
How it compares with the other picks
On our battery coffee maker comparison, the closest rival is OutIn's own first-generation Nano. OutIn says the Nano 2 has twice the endurance of the Nano 1, charges in about 100 minutes against 180, and has a larger 8-gram basket. It also lists the Nano 1 Basket Plus as incompatible with the Nano 2. The Mino is a smaller model in the same line. If you are cooking rather than brewing, see our cooking without power guide.
Verdict and who should skip it
A tidy way to make a hot espresso during an outage, if you can keep a power bank charged and bring safe water. OutIn lists a 12-month limited warranty. Skip it if you need to make more than a small cup at a time, if you cannot supply 45 W of USB-C charging, or if you want a way to heat water for a household, because it is not built for that.
A researched review, built from the maker's specs, manual and US listings; facts checked 2 Nov 2026. Sources: OutIn: Nano 2 Portable Espresso Machine product page; OutIn: Nano 2 FAQ; EPA: Emergency Disinfection of Drinking Water.
Who shouldn't buy this
Don't buy it if you need hot water for the whole household: a camp stove and kettle, used outdoors, boils a quart at a time for much less.
Key specs
| Heats its own water (maker's figure) | Yes: 120W heater, room-temperature water hot in as little as 159 seconds (OutIn's lab figure) |
| Cups per charge (maker's figure) | Up to 9, heating 50 ml from 77°F to 199°F each time; over 600 with water that's already hot (OutIn's lab figures; 5,000mAh, 54Wh battery) |
| Charging | 45W USB-C PD, full in about 100 minutes |
| Water per cup | 85 ml (about 2.9 fl oz) tank; ground coffee (8 g basket) or Nespresso Original Line-compatible capsules |
This is a Researched review: we haven't used this product. We check every specification against at least two independent sources, re-check the US price on a schedule where we can track it automatically, and say plainly who it isn't for. Commissions never change a rating.
If this isn’t the one
Best for A tough, pocket-sized espresso maker for the car, the RV or a go-bag
Best for The lowest-priced self-heating OutIn, for an occasional cup
Questions
How many cups does the OutIn Nano 2 make per charge?
OutIn says up to 9 cups heating 50 ml of room-temperature water, and over 600 extractions with already-hot water. Those are the maker's lab figures, and real results vary.
How do I charge it during a power outage?
Use a USB-C power bank or power station. OutIn recommends a 45 W USB-C PD adapter, says a full charge takes about 100 minutes and warns that 5 W phone chargers may not work well.
Can it purify water?
No. OutIn does not describe it as a water treatment device. EPA says to use only properly disinfected water for any prepared drink, so start with boiled, bottled or treated water.
Can I use it while it is charging?
No. OutIn says not to operate the Nano 2 while it is charging, because brewing and charging together may activate its over-temperature protection.