Portable oxygen concentrators don’t get any more portable than the Inogen One G4. At just 2.7 pounds, it’s one of the lightest O2 machines on the market that meets FAA requirements, making it one of the best options for people who are on the go.
Inogen, a leading global medical technology company with offices in Goleta, California, and the Netherlands, has been producing innovative, best-in-class portable oxygen concentrators since 2001. They operate distribution centers worldwide and have sold more than 1 million portable oxygen concentrators in 59 countries to date. Inogen’s high-quality devices frequently land them at the top of best-of lists.
As a top name in portable oxygen concentrators, the Inogen One G4 is often prescribed by medical providers to patients who have trouble breathing due to medical conditions like COPD and emphysema. With its reliable brand name and highly compact size, it’s our top pick for the most portable option for travel.
Inogen One G4 portable oxygen concentrator: Pros and cons at a glance
| Pros | Cons |
| One of the lightest portable O2 machines at just 2.7 pounds with a single battery. | Only three flow settings. |
| Fits in the palm of your hand: 7.2ʺ × 5.91ʺ × 2.68ʺ with a 4-cell battery. | Flow rate of up to only 630 mL of oxygen per minute. |
| Three-year warranty with the option to upgrade to a lifetime warranty. | 4-cell battery lasts up to only 2 hours and 40 minutes. |
| Approved by the FAA for air travel. | No specialized travel adapters designed specifically for the G4 oxygen machine. |
| Office-quiet 40 dBa on setting 2. | 8-cell battery costs extra. |
| Connects to your smartphone with the Inogen Connect app. | No option to purchase a 16-cell battery. |
| Option to purchase an 8-cell battery that lasts up to five hours. | |
| Can be used when plugged into a wall outlet, even when the battery is fully charged. |
Key features and specifications
Dimensions: 7.2ʺ × 5.91ʺ × 2.68ʺ with 4-cell battery; 7.9ʺ × 5.91ʺ × 2.68ʺ with 8-cell battery
Weight: 2.7 pounds with 4-cell battery; 3.3 pounds with 8-cell battery
Battery life: Up to 2 hours and 40 minutes with 4-cell battery; up to 5 hours with 8-cell battery
Oxygen delivery mode: Pulse
Oxygen flow rate: Three settings delivering up to 630 mL of oxygen per minute
Noise level: 40 dBa on setting 2
Cost: Starting at $2,744.00
Additional features of the Inogen One G4 portable oxygen concentrator
The Inogen One G4 is easy and intuitive to use with a large screen that displays important information like the oxygen flow setting and remaining battery life. You can also easily read it at night: Briefly press the power button, and the screen will illuminate for 15 seconds.
The Inogen One G4 uses visual and auditory alarms to alert you to potential problems. A green light tells you the device is functioning properly, while a yellow one with audible beeping indicates an issue, such as if the device doesn’t detect a breath or if the cannula needs to be replaced. If the lights are flashing and the beeping is repeating, there is a high-priority issue that requires quicker attention, such as an overheating device or an empty battery. Messages are displayed clearly on the screen so you can see exactly what the issue is at a glance.
The Inogen One G4 can be used when plugged directly into a wall outlet, which is handy if you’re using your machine at home and don’t want to waste the batteries. You can also run the machine using electricity while you sleep without worrying about having to replace a dying battery in the middle of the night.
Inogen offers an app that makes managing your device easier. Called Inogen Connect, it allows you and your care team to monitor battery life and flow settings, receive maintenance information, and more.
The app includes quick FAQs about Inogen and your device, but you can also find online materials like manuals, setup videos, and FAQs on their website. It’s a handy way to learn more about the G4 before purchasing. You can also quickly look up information after you have purchased the machine.
Accessories
The Inogen One G4 comes with accessories that include:
- One 4-cell battery.
- Carrying bag and strap.
- AC power supply cord.
- DC power supply cable.
- Nasal cannula.
Inogen offers a few additional accessories for its G4 unit. They include:
- Additional 4-cell and 8-cell battery packs.
- Additional particle filters.
- Additional AC and DC power supply cords.
- External battery charger.
- Replacement columns (also known as sieve beds, the filters that separate oxygen from the air).
- Backpack.
- Hip bag.
You can also find special airline bundles since the Inogen One G4 is such a popular choice for travelers. For example, Main Clinic Supply offers a bundle that includes a backpack, an external battery charger, one or two 8-cell batteries, and an airline priority tag that excludes your device from regular baggage fees.
Oxygen delivery modes
The Inogen One G4 uses Intelligent Delivery Technology to provide medical-grade oxygen in pulse doses. This proprietary technology ensures that oxygen is delivered within the first 250 milliseconds of inspiration, when oxygen has the greatest effect on your lungs. It effectively provides concentrated oxygen during sleep, rest, regular activities, and exertion.
The device delivers an oxygen purity level of 90%, which is average for the industry, at a flow rate of up to 630 mL per minute. Oxygen is delivered in pulses when you inhale, which the machine detects. It features three different pulse dose settings that should be set according to your prescription.
For each setting, the oxygen amount increases in liter increments of 210 mL per minute:
- Flow setting 1: 210 mL per minute.
- Flow setting 2: 420 mL per minute.
- Flow setting 3: 630 mL per minute.
Oxygen delivery is personalized based on your breathing rate, delivering different amounts of oxygen according to your breaths per minute (BPM). The slower you breathe, the larger the burst (bolus) of oxygen per breath. Faster breaths generate smaller bursts of oxygen. This automatic adjustment ensures that you get the proper dose of oxygen per minute.
| Flow setting | 10 BPM(mL/bolus) | 20 BPM(mL/bolus) | 25 BPM(mL/bolus) |
| 1 | 21.0 | 10.5 | 8.4 |
| 2 | 42.0 | 21.0 | 16.8 |
| 3 | 63 | 31.5 | 25.2 |
Inogen One G4 portable oxygen concentrator cost
There are a few different ways to purchase an Inogen One G4 portable oxygen concentrator. Learn more about your options below.
Buy it new
Inogen doesn’t sell their G4 portable oxygen concentrator directly. Instead, they recommend that you purchase your device from authorized internet resellers. Inogen authorizes only three other companies to sell their products. They include:
- Main Clinic Supply.
- OxiMedical.
- American Medical Sales and Rentals, which sells the product through the Oxygen Concentrator Store.
The minimum starting advertised price is $2,744.00, which is pretty average compared to other devices on the market from trusted brands. You may pay more depending on the accessories you choose. For example, the 8-cell battery costs an extra $618.00 at the Oxygen Concentrator Store.
Inogen One G4 portable oxygen machines come with a three-year warranty when purchased from an authorized dealer. Depending on where you shop, you may be able to upgrade to a lifetime warranty. For example, if you choose the platinum bundle from Main Clinic Supply, you’ll receive columns, intake filters, and output filters annually for free for life.
You can make your O2 machine more affordable by choosing a payment plan, which all three of Inogen’s approved sellers currently offer.
Buy a refurbished machine
You can purchase preowned, certified machines that cost less. For example, the Oxygen Concentrator Store offers a recertified Inogen One G4 concentrator for just $1,500. Just look carefully at the warranty options offered by each retailer. You may have to pay extra for warranty coverage on a refurbished machine.
Rent before you buy
Inogen’s three authorized sellers don’t currently offer rentals for the Inogen One G4, but you can find other outlets that will let you rent the machine. My Medical Outlet rents the Inogen One G4 for one month for just $449, which is a great way to try before you buy.
Battery life
One of the biggest downsides of the Inogen One G4 portable oxygen concentrator is that the battery life is somewhat short. The single 4-cell battery doesn’t last long, especially compared to some other portable oxygen concentrators on the market. It lasts:
- 2 hours and 40 minutes on setting 1.
- 2 hours and 15 minutes on setting 2.
- 1 hour and 20 minutes on setting 3.
The 8-cell battery makes the device a bit larger and heavier, but it might be worth it if you plan to be out and about for longer periods. Upgrading to the 8-cell battery gives you extended battery life at:
- 5 hours on setting 1.
- 4 hours and 30 minutes on setting 2.
- 2 hours and 30 minutes on setting 3.
Charging options
The 4-cell battery takes approximately three hours to charge, while the 8-cell battery takes approximately five hours. Batteries can be charged when attached to the O2 machine while it’s plugged in, but it’s a good idea to purchase an external battery charger so you can charge an extra battery while using the machine.
You can check the charge by pushing the green battery icon button on the battery. LED lights indicate how much life it has left. You can also check the charge on your battery while it’s plugged into your portable O2 concentrator. The screen will show you if your battery is charging, full, has approximately 50% charge remaining, or has less than 10% charge remaining.
An AC power supply cord that plugs directly into a wall outlet is included. If you’re traveling abroad, you’ll want to purchase a converter. Unfortunately, Inogen does not sell a special travel adapter. Instead, you’ll have to buy a generic travel adapter, which can be found on websites like Amazon.
The portable oxygen concentrator also comes with a DC power cord that can be plugged into your car. However, multiple users have mentioned that the cord gets very hot. If you want to be able to charge your device in the car, one user recommends getting a DC converter and plugging your regular AC charger into the converter instead of using the provided DC power cord.
Portability and design
What the Inogen One G4 lacks in battery life and oxygen settings, it makes up for in size. It is the smallest and lightest portable oxygen concentrator on the market offered by a reputable brand.
It weighs only 2.7 pounds with the included 4-cell battery, which is about as heavy as a pineapple. At just 5.91 inches long by 2.68 inches wide by 7.2 inches high, it easily fits in the palm of your hand. It’s so small it can easily fit inside a backpack or a fanny pack, and it takes up almost no room at all in a carry-on bag, making it the ideal option for users who do a lot of traveling.
It also doesn’t require a cart. Instead, it comes with a shoulder bag, but you can also purchase a backpack or hip bag, depending on how you want to carry your machine. The FAA has preapproved it for air travel. All you have to do is notify the airline that you’ll be using oxygen, and your machine won’t count toward your carry-on count or baggage fees.
If you plan to travel extensively with your Inogen One G4, we recommend purchasing multiple batteries to ensure you always have access to oxygen. Bring your AC charger and external battery charger in your carry-on bag so you can charge batteries while waiting for your next flight in the airport if needed.
Setup of the Inogen One G4 portable oxygen concentrator
The Inogen One G4 is easy to set up. First, slide the battery into the bottom of the concentrator and make sure the particle filter is in place on the side of the machine. Then, plug the AC power adapter into the bottom of the concentrator and into an electrical outlet. Connect the nasal cannula on the top of the machine and attach it to your nose. Push and hold the power button for one second to turn the machine on. Once it’s on, you can set it to the oxygen level prescribed by your doctor. You can check out a step-by-step video to see exactly how to set up the G4 in your home for the first time.
You can use the machine while it’s plugged in and the battery is charging or fully charged. It does not harm the concentrator or the battery. That’s handy because you can plug your device directly into the wall whenever you have access to an outlet and save the battery for when you’re out and about.
Operation guide and assistance
To learn more about operating the machine, you can check out Inogen’s complete online library of manuals. Authorized sellers of Inogen’s oxygen machines can also be a good resource. For example, the Oxygen Concentrator Store has a handy library of educational videos.
Warranty
Inogen offers a three-year warranty on the G4 device with the option to upgrade to a lifetime warranty. When you purchase your machine from an authorized dealer, your warranty kicks in as soon as it is shipped.
In addition, an authorized dealer can help you understand what’s included in your warranty and what additional warranties you may want to include with your purchase. For example, Main Clinic Supply offers upgraded warranties that cover the replacement of parts like columns and intake filters. They also offer drop coverage that will cover the repairs on your machine if you accidentally drop it.
You may want to consider upgrading to a lifetime warranty or an additional warranty through the retailer where you purchase your machine if you plan to use it for a long period of time. The Inogen One G4 has an average lifespan of five years. Sieve beds have an expected lifespan of one year. Batteries can be fully charged and discharged an average of 500 times before they need to be replaced. If you think you’ll own the machine for more than five years or don’t want to have to worry about paying to replace sieve beds, paying extra for a more robust warranty might be worth it.
Maintenance and care instructions
The Inogen One G4 is relatively easy to maintain. The air intake filter on the front of the device should be cleaned with a mild liquid detergent, like Dawn, once a week. Make sure the filter is completely dry before reusing it.
The sieve beds in your portable oxygen concentrator should be replaced every 12 months. When they need to be replaced, the machine will display a “Replace Columns” message. It’s a relatively straightforward process that you can do yourself. You can find the step-by-step process for replacing the columns here.
Never submerge the oxygen concentrator or its accessories in water. Instead, wipe the casing with a damp cloth. Avoid using alcohol, isopropyl alcohol, ethylene, or petroleum-based cleaners, as they can damage the case and filters and affect the machine’s operation.
Nasal cannulas should be replaced more regularly according to your physician’s recommendations and the manufacturer’s instructions.
Troubleshooting common issues with the Inogen One G4 portable oxygen concentrator
The screen on the Inogen One G4 displays intuitive, easy-to-read icons, messages, and warnings that identify any issue your machine may have. For example, a triple beep accompanied by a flashing yellow light and a message that reads “No Breath Detect: Check Cannula” indicates that the machine can’t detect your breathing rate. In this case, you should ensure the cannula is connected to the concentrator, there are no kinks in the tubing, and the cannula is properly positioned in your nose. You can learn more about all the machine’s visual and audio alerts in the manual.
If you’re having trouble operating your machine, the Oxygen Concentrator Store has a helpful list of common oxygen concentrator malfunctions and how to address them on their support page. If you’re still having trouble, consider directly contacting the store where you purchased your O2 machine. Most retailers have customer service teams that can help you troubleshoot problems or determine whether you should send your device in for a repair or get a replacement.
Safety considerations
The Inogen One G4 is designed to be safe to operate, but there are some precautions you should take when using an oxygen machine, no matter which brand or model you’re using.
Although oxygen isn’t flammable in and of itself, fire needs oxygen to breathe, and it can cause a spark or fire to spread. You should never smoke near your machine, and any sources of heat or flame should be at least five feet away from the unit. Consider using a humidifier if you live in a dry climate in the winter, and put cotton sheets on your bed to avoid static, which has the potential to cause a spark. You should have a fire extinguisher handy at all times if you use an oxygen concentrator, just in case.
Click here for more portable oxygen concentrator safety tips.
Customer service
Before you contact Inogen directly, it’s a good idea to reach out to the retailer where you purchased your machine. They can provide targeted customer service because they have your purchase information on file. They can also help you understand your warranty and troubleshoot problems over the phone.
If you purchase your oxygen machine from OxiMedical, you may be able to get help in person, depending on where you live. They have physical stores in Glendale, Arizona, Denver, Colorado, and Delray Beach, Florida. If you live nearby, you can shop for a portable oxygen concentrator at one of their stores or take your machine in and have a store associate help you troubleshoot problems.
You can also contact Inogen directly at 1-855-694-6643 if you need help with your machine. They may be able to answer your questions but may refer you to the retailer you purchased your machine from for replacements and repairs.
User reviews and testimonials
The reviews on Inogen’s website can help you learn more about how users feel about the Inogen brand. Their reviews are broken into caregiver and customer categories. Just keep in mind that these reviews include all Inogen machines, and some reviews don’t mention which model the customer uses. Also, Inogen posts only positive reviews.
If you want a more honest assessment, check out the reviews at the Oxygen Concentrator Store. Not only are they specific to the Inogen One G4 portable oxygen concentrator, but you’ll also find slightly more honest reviews. This O2 machine has a 4.6-star rating, which is very good, but a few users mention that the machine is louder than they expected or that they were disappointed in the design of the carry bag.
Keep in mind that retailer reviews may also include thoughts about the company in addition to information about the device. Some retailers, like Main Clinic Supply, lump all their reviews together, which means you don’t necessarily know which product the user is reviewing. This information can be helpful if you’re trying to determine where to purchase your machine, but it can make finding relevant information more difficult if you want to learn more about a specific concentrator.
How to buy the Inogen One G4 portable oxygen concentrator
Inogen sells some products directly on their website, but they do not sell the Inogen One G4. Instead, you have to purchase your machine from a medical equipment supplier. It’s recommended that you purchase your machine from an authorized Inogen seller. Inogen has a clear internet resellers policy that lists which sellers are authorized by them to sell Inogen machines. They include:
- Oxygen Concentrator Store (American Medical Sales and Rentals).
- Main Clinic Supply.
- OxiMedical.
Pricing starts at $2,744.00, which is the lowest advertised price for the Inogen One G4. However, you may be able to get a better deal depending on where you purchase your machine. For example, OxiMedical advertises matching or beating the price of any authorized dealer plus an extra $200 off, but you have to contact them and request a quote, which can be a hassle if you want to purchase a brand-new machine online without having to speak to a customer service representative first.
If you’re looking for other ways to save some money, you might consider purchasing a refurbished system. The Oxygen Concentrator Store has one for $1,500. Not all retailers offer the same accessories as when buying a new machine, so look closely at the fine print to make sure you’re getting what you need (battery, power cord, etc.).
Keep in mind that the original three-year warranty may also be void if you purchase a refurbished machine. If you want protection from defects, you may have to pay extra for a one- or two-year warranty.
If you already have a portable oxygen concentrator, you could save on a new machine by trading in your old one. Some retailers offer buyback programs, which is a nice way to upgrade from an old machine and save a little money.
Final thoughts on the Inogen One G4 portable oxygen concentrator
If you’re looking for the lightest reliable oxygen concentrator on the market, consider the Inogen One G4. It weighs less than 3 pounds and is comfortable to carry in a shoulder bag, backpack, or hip bag. With AC and DC cords, charging your portable oxygen concentrator at home and on the go is easy. Because it’s approved by the FAA for air travel, it’s also one of the most convenient O2 machines for traveling.
Although the Inogen One G4 offers lower oxygen flow rates and fewer pulse dose settings than some other machines, it could be the perfect choice for those with lower oxygen needs who prioritize staying active.
