After researching more than two dozen models, interviewing experts, and having an electrical engineer test our top candidates, we found that the CyberPower CP685AVR is the best uninterruptible power supply (UPS) for people who want to keep a home network running during a blackout of an hour or less. It’s easy to set up, it has some of the most positive user reviews in its class, and it’s the most affordable unit we found. We also like the APC BE650G1 Back-UPS, if it’s available for less. But if you need to power more than a modem and a Wi-Fi router—say, to keep a desktop computer running long enough for you to shut it down safely—or if you need to stay online longer, the APC BR1000G Back-UPS Pro is a better choice, with more than twice the power for less than twice the price.
*At the time of publishing, the price was $68.
The CyberPower CP685AVR will cover the basics for most people during common, short blackouts. In our tests it provided enough power to keep the average cable or DSL modem and Wi-Fi router running for an hour, which means you can stay online to while away the time while the lights are off—or, in a real emergency, keep your digital phone service powered so you can reach the outside world. The size of an overgrown surge protector, the CP685AVR is small enough to hide in the same corner as your networking gear, and since it has surge protection built in, you’ll have one less thing to buy. Although you could easily spend more on a UPS, you really have no reason to if you need only basic, noncritical protection and a limited amount of power.
When we tested the CyberPower CP685AVR alongside its closest competitor from APC, the APC BE650G1 Back-UPS, the CyberPower lasted longer and stayed truer to its stated rating, but the difference was less than five minutes of uptime on average—59.6 minutes of power versus 55.8. The similarities between the APC and the CyberPower don’t end there: Both units have surge protection on all eight outlets, with four of those outlets covered by the battery-backup protection. Both lack any sort of status display, though you can monitor and manage either device by connecting it to your computer via USB and installing proprietary software. The two systems even have the same three-year warranty. The CyberPower is our top pick, and it’s often a few dollars cheaper, but if you can get the APC BE650G1 for less, it will serve you just as well.
If you’re going to have more devices plugged in—for example, your desktop computer and display—or if you need to be able to use them longer in a power outage, the APC BR1000G Back-UPS Pro offers some extra juice and is an excellent value. It’s almost twice the price of our top pick from CyberPower, but it will last more than twice as long when powering a 50-watt load such as a modem and Wi-Fi router—about 2 hours, 15 minutes in our tests. And if you have a workstation or some other high-power draw, such as audio equipment or a large display, you should step up to this size of UPS at a minimum. Even with its larger battery, the BR1000G can keep a 300 W load like a desktop computer and peripherals running for only about 15 minutes. That may not get you through a long blackout, but it is enough time for you to finish an email, save your game progress, or check in with coworkers before being banished from the connected world.
This kind of battery-based power-backup system, called an uninterruptible power supply, is basically a surge protector, a battery, and a power inverter (which turns the battery’s stored energy into usable power) wrapped into one unit. Consider this: When you stream an online video to your computer or phone, the video player first takes a few seconds (or minutes) to get some of the video data into a buffer so that if your Internet connection is inconsistent while you’re watching, you still get smooth playback. A UPS is a similar buffer but for your electricity, in that if your power dips temporarily or goes out completely, anything plugged into the UPS can continue to draw power from the buffer, unaware of a problem. Although the buffer—the battery inside the UPS—will eventually run dry, it should keep you online during short blackouts.
For many people, a UPS falls into the murky gray area between need and want. If you have a desktop computer or network-attached storage, you may need a UPS to prevent your drives from losing data in the event of a sudden power outage. And if you have digital phone service through your broadband provider, and the company skimped on your equipment by not including a battery, you may need a UPS to power your phone modem during a blackout so that you can reach emergency services. But a UPS is also handy during mundane power outages, since it allows you to pass the time on Facebook or Netflix while you wait for the juice to return. (If you’re the only one in the area with a working router during a blackout, you’ll earn some major karma points for creating an unsecured guest network and naming it “Free Wi-Fi during power outage.”)
A UPS makes sense in a lot of scenarios, but not in all of them. If all you’re looking for is surge protection, you have no need to spend money on a bulky UPS when better and less expensive surge-protection options are available. Neither is a UPS the right choice to keep an extensive home theater powered up, or to run most any household appliance—the UPS units we’re covering here don’t provide enough power. If your needs are on that scale, you might want to consider a home generator, or a battery system designed for off-grid power. Similarly, if you’re trying to figure out how to power electronics far from the grid, companies such as GoalZero and Renogy offer a more appropriate option.
To find the best UPS for most people, we looked at the power output, battery capacity, and user comments on 28 of the highest-rated and most-popular UPS options on Amazon. The field mostly consists of products from established brands such as APC, CyberPower, and Tripp Lite, with a few smaller brands sprinkled in.
When you’re deciding what size UPS you need, you’re actually assessing two different things: power output and battery capacity. Most UPS models have their maximum output, rated in volt-amps (VA) or watts (W), right in the name. But that number indicates only how many watts the UPS can provide—that is, how much gear you can plug in—at once. How long the battery lasts will depend on how much gear you connect to it: The more devices the battery has to power, the less time it will give you. As you move up in maximum output, battery capacity sometimes follows, but not always. Since different manufacturers match output and capacity at different ratios for a given price, it’s important to find and compare both ratings.
For our pick, which we chose based on the product’s ability to keep a home network up and running, maximum output was less of a concern than capacity. A combination of a 60 W modem and router won’t be a problem for even basic UPS units, which tend to put out around 350 VA (roughly 200 W). So instead of focusing on output ratings, we focused on capacity—specifically, how long each UPS could keep 50 W of equipment running.
Every UPS we looked at includes a data port in case you want to install monitoring software, but monitoring features are a convenience rather than a necessity. For example, you can configure software on your Windows or macOS computer to automatically shut the computer down safely if the power goes out. While higher-end UPS models have additional options, such as LCD monitoring or pure-sine-wave inverters, those upgrades aren’t worth the investment for most people seeking a basic battery-backup unit for a home network.
We also looked for models with the additional power output and capacity that a workstation UPS needs. CyberPower representatives told us that its most popular range of products tends to provide around 1,500 VA. For many people, however, even that looks like overkill when you do the math. When we tallied up the power consumption of a modern tower desktop (around 150 W), our favorite 27-inch monitor (88 W maximum), our favorite hard drive (10 W to 15 W), and the same modem and router we used as a guideline for our top pick (60 W), we barely pushed past 300 W. Since most residential UPS options in this range have only four battery-powered outlets anyway, you’re unlikely to need a much higher output than that.
However, to get reasonable run times—in other words, to keep that 300 W load running long enough—we found that it was worthwhile to move up to around 1,000 VA, or about 600 W. With a UPS of that size, you’ll generally get 15 minutes or so to finish your current task and power down a 300 W rig, or a couple of hours to keep 50 W of Wi-Fi gear running. At the 600 W size, you won’t see much of a price difference between units with or without an LCD to monitor the UPS’s status, and since a workstation UPS is more likely to be in a visible location near your computer, we decided to rule out any workstation models that didn’t include an LCD.
For each tier, network, and workstation, we settled on a pair of devices to test, one each from APC and CyberPower, the largest and most popular manufacturers in this performance range. Models such as the AVR650UM from Tripp Lite cost more and had fewer reviews, while offerings from Eaton were more expensive and harder to find since they weren’t intended for home use. In the end, the model variations from APC and CyberPower had the broadest appeal. And these models not only fit our basic output and capacity requirements but also had detailed, positive user reviews. They offered some of the best dollar-per-minute measures of value, too. We sent all four—the CyberPower CP685AVR, the APC BE650G1 Back-UPS, the CyberPower BRG1000AVRLCD, and the APC BR1000G Back-UPS Pro—to an electrical engineer, Lee Johnson, who set to work testing them and disassembling them to assess the quality of their components and construction.
Because most electronics vary their energy consumption depending on their task—your laptop, for instance, uses more power when the processor is working hard and the fans are spinning, and your router does so when it’s managing multiple connections—we decided to build a test rig that provides a more consistent load than, say, a laptop or router. Our engineer, Lee Johnson, wired up 10 light sockets to accept 50 W halogen bulbs, added a USB data logger to track run time, and used a Kill A Watt meter combined with a true-rms multimeter and an oscilloscope to verify the power levels, giving us the option to replicate tests as necessary.
|50 W load||300 W load|
|Time to shutdown (in minutes, to nearest second)||Time to shutdown (in minutes, to nearest second)|
|Model||Test A||Test B||Test C||Average||Test A||Test B||Test C||Average|
|APC BE650G1 Back-UPS||53.9||58.5||55.1||55.8||5.5||5.7||5.6||5.6|
|APC BR1000G Back-UPS Pro||131.1||133.3||138.1||134.2||17.0||15.9||16.3||16.4|
We allowed each UPS unit to charge for 12 hours before each test. We first gave each UPS a 50 W load until it shut down, repeating the test three times. We then repeated the process at 300 W. When we averaged our results, the data showed clear winners for both classes, though a different brand won each class.
Every major UPS comes with some basic surge protection built in, which is good because you can’t plug your UPS into a surge protector, or plug a surge protector into a UPS. Unfortunately, most affordable UPS units don’t offer much protection compared with a dedicated surge protector: Lee Johnson took apart our samples and found only basic protections inside—the APC BR100G should protect your equipment about as well, if not as long, as basic surge protectors we’ve tested before.1 It also has the advantage of extra capacitors and filtering circuits to help keep the power steady. The CyberPower CP685AVR won’t take as many hits, nor ones as large, but both the APC and CyberPower models have the advantage of an extra transformer that acts as a buffer between the wall and your gear.
This transformer creates what’s called line interactive topology, which manufacturers sometimes market as automatic voltage regulation, or AVR. If the voltage from your home sags or swells within a certain range, the transformer corrects it for your equipment without the UPS needing to switch to battery or divert power to the surge-protection circuits. Economy models, in contrast, use what’s called standby topology, which switches to battery backup for even small power problems, switching more slowly and causing more wear on the cells—and potentially on your connected equipment—over time.
*At the time of publishing, the price was $68.
The CyberPower CP685AVR is our first choice for anyone who wants a UPS to keep their home network and modem online until the power comes back up, though the APC BE650G1 Back-UPS is nearly identical in performance and is just as good of a pick if you happen to find it for less.
Most people are looking for a UPS to solve one of three problems in a blackout: powering a digital-phone modem for contacting emergency services and loved ones, preventing damage to something that needs to be properly shut down, or passing the time until the electricity comes back. The CP685AVR can keep a combination of a common 50 W cable or DSL modem and Wi-Fi router on for about an hour, or a 300 W workstation online for a few minutes while you frantically save work and safely shut everything down. Even though power outages have increased in some parts of the US in recent years, they tend not to last too long (PDF), so a basic UPS should get you by in even the most unreliable regions.
We tested the CP685AVR against APC’s closest competitor, the BE650G1. Though the APC unit had a much longer advertised rating at a 50 W load—87 minutes versus 59 minutes—the CyberPower unit edged it out in our real-world tests, averaging 59.6 minutes compared to APC’s 55.8 minutes. We ran each test three times on a single sample of each device, so numbers this close are not definitive, but in the end the CyberPower unit performed to its rating while the APC unit underdelivered, despite the tie. Without any other differentiating factors, that’s just enough of an advantage to make the CyberPower CP685AVR, which is often a few dollars cheaper, our top choice. But if our top pick is out of stock or the price goes up by more than a few dollars, we wouldn’t hesitate to pick up the APC BE650G1 instead.
You won’t find many in-depth editorial reviews of the CP685AVR or most other battery-backup units. UPS comparison isn’t a sexy topic, and the units aren’t easy to test. But the company’s AVR Series has user reviews dating back almost 10 years. Although we’ve become wary of user-review averages for some product categories, CyberPower isn’t a no-name brand, and the UPS’s review distribution is what we expect to see for a good product with fair reviews—mostly five- and four-star ratings, trailing off until you get to a slight uptick of one-star reviews that (in our experience with customer reviews) often overrepresent the rate of failure. For the most part, users have found the CyberPower offering to be a competent UPS, which is about what you’d expect for a utilitarian device.
Our simulated workstation, drawing 300 W of power, was near the maximum output of both units. However, although each model is technically capable of providing that much output, we don’t recommend using more than 50 percent of a UPS’s maximum output if you want to get the best performance—real-time or long-term—out of the battery. Since battery life isn’t linear, a slightly higher draw can lead to a greatly reduced run time. Though both models in our tests ran a 50 W load for almost an hour, when powering our 300 W load the APC BE650G1 averaged only 5.6 minutes and the CyberPower CP685AVR squeaked out just 4.6 minutes. As with the 50 W test, these results are close enough to be a tie—in either case, that’s just enough time for you to quickly save your work and safely shut your computer down. (A small UPS simply isn’t meant for this level of power, so if you expect to draw over 100 W, you should step up to our more powerful pick instead.)
The other similarities between the CyberPower and APC units outnumber the differences. Both devices provide eight outlets, four of which have battery backup and surge protection, while the other four offer only surge protection. Both units have all the appeal of a rectangular block and lack any screen or status display. If you want to monitor or manage either one, you’ll need to connect it to your computer with a USB device cable and install the included software—a feature that CyberPower’s director of product management, Tim Derochie, told us is used by only a small minority of home customers. Though CyberPower’s model can provide 15 W to 20 W more power than the APC device, that doesn’t mean much in the real world. If anything goes wrong, both companies provide a three-year warranty.
At this level, a UPS is a basic, utilitarian device, and both APC and CyberPower are reputable companies. Either device offers set-it-and-forget-it protection and will keep your gear going for about the same amount of time during the next blackout. When Amazon has both models in stock, their prices tend to be only a few dollars apart. If you use dollars per minute as a measure of value, that puts them both in the ballpark of $1.15 per minute of battery-backup capacity for a home Wi-Fi network. Pick the cheaper one, and you’ll have some peace of mind the next time a thunderstorm rolls in.
If you want to keep your network up for more than an hour in a blackout, or if you plan to have 100 W to 300 W worth of stuff plugged in to your UPS, the APC BR1000G Back-UPS Pro is the way to go. This 24-pound minitower, measuring 3.9 inches wide, 9.8 inches high, and 15 inches deep, holds a higher-capacity battery and higher-output inverter capable of around 600 W. In our tests, the APC BR1000G lasted almost twice as long as the similarly priced CyberPower BRG1000AVRLCD.
Though it seems like a 300 W model should be able to run a 300 W load, the reality is that the battery in such a small unit will run down in a frustratingly short time. If you want to have the power to do anything more than save your work, you shouldn’t load a UPS with more than 50 percent of its rated output. This means that if you’ll be plugging in around 300 W worth of equipment—that’s a desktop computer, a 27-inch LCD monitor, an external hard drive, a cable modem, and a wireless router, with some room to spare—your UPS should be rated around 600 W or more.
To quickly convert an advertised volt-amp rating to something more useful, you can cut the VA figure in half to get the rating in watts and then cut it in half again to estimate the load that you’ll be able to run for a reasonable amount of time. So a 1,200 VA UPS might be rated for about 600 W, which would be about right for a 300 W workstation. Such an estimate errs on the safe side to make the calculation simple, since a truly accurate calculation depends on which variable you put into an engineering equation that you don’t really have to care about. (If you do care about it, the real power in watts is equal to the apparent power in volt-amps multiplied by the power factor, or W=VA × PF. We also discuss the VA rating a bit more below.)
Even with higher loads, the APC BR1000G performed well in our tests. With a 16.4-minute average, it bested its advertised 14-minute rating by a couple of minutes, while the CyberPower model averaged only a little over 7 minutes of run time with our 300 W load. When the power goes out, a few extra minutes make a big difference: You can finish the email you’re typing, shut a set of spinning NAS drives down, or double-check one last document.
If you’re running only your network equipment, the amount of extra time you get is even more dramatic. The APC BR1000G ran for an average of about 134 minutes with our simulated 50 W network-equipment load, almost twice as long as the CyberPower BRG1000AVRLCD, which lasted for nearly 72 minutes. Based on those results, at the time of this writing the APC costs less than a dollar per minute of backup power, making it an even better value than our home-network pick. Though the prices of both workstation units regularly fluctuate, they generally do so by only a couple of dollars.
As with our smaller picks, few editorial reviews or tests are available for the APC BR1000G. But even though this model hasn’t been around as long as our smaller-load pick, it has gained quite a following, with almost 2,000 user reviews on Amazon dating back to 2010. Users report similar pros and cons for this unit as for our other picks: It does what it claims to do, it isn’t a great surge protector, and it might not work with high-end desktop PCs. When you keep those realistic expectations in mind, the BR1000G is great for what it’s supposed to be.
Once you’ve decided to spend more than $100 for a UPS, getting a model with a status display doesn’t cost much more than a unit without one, and such displays are convenient. Talking about the APC BR1500G, a larger model with the same display as the APC BR1000G, Wirecutter editor Dan Frakes said, “The LCD is really useful for seeing how much estimated time is left, viewing the battery charge level, and getting diagnostic info. All my UPS units have LCDs now, and I wouldn’t want one without a display.” Below its display, the CyberPower BRG1000AVRLCD has USB outlets that the APC BR1000G lacks, but with the latter model, that’s a small sacrifice for such a huge performance gain.
The APC unit clearly performed better in our tests, but the rest of its feature list is common among UPS models in this price range. The APC and the CyberPower each have four outlets protected by battery and surge protection, along with four that provide only surge protection. Both companies supply proprietary software that you can install to monitor your UPS over USB, as well as to set the software to safely and automatically shut your Windows computer down during a blackout. (Apple’s macOS includes a built-in feature that does the same thing when the UPS is connected via USB.) CyberPower does offer a five-year warranty versus APC’s three-year coverage, but we’ll take the performance gains of the APC model over two years of extra protection for a unit that doesn’t perform as well.
It’s important to know what a UPS can’t do. High-drain devices—including large office equipment such as laser printers and paper shredders, as well as anything that makes heat, like a space heater or curling iron, or any type of medical equipment—can damage a UPS’s components and degrade its battery. Such use may also void the UPS’s warranty. Small electronics or office equipment without moving parts should be fine, but for anything bigger, check the UPS’s manual.
Do not ever—ever, ever—plug a UPS into a surge protector, or plug a surge protector into a UPS. Aside from potentially overloading either unit and tripping a fuse or breaker, you also risk canceling out the surge protection function instead of doubling it up. Tim Derochie at CyberPower told us that UL, the independent company that evaluates electronics safety, strictly forbids the practice, and you’ll find strong warnings against the practice in user manuals.
The sealed, lead-acid battery inside your UPS will stay charged as long as the device is plugged in, so it should be able to perform well for many years. But because batteries degrade over time, you can avoid any surprises in the future if, once a year or so, you unplug it with your devices running to make sure it powers them as long as you expect it to.
A volt-amp is equal to power (in watts) divided by a power factor (a measurement of how well a device turns the apparent power of a circuit into real power). But don’t get too hung up on a UPS’s VA rating—instead, look for a wattage rating buried in the product listing or, if you can’t find the wattage rating, assume that it’s half the VA rating.
If you’re interested in electrical theory, or comfortable with algebra, here’s the background on why this is the case: In basic electrical theory, watts (W) = volts (V) × amps (A). Except AC-powered electronics are more complicated than that, so in actuality, watts = volts (V) × amps (A) × power factor correction (PF). Often, PF = 1, which means that VA does indeed equal W. But sometimes PF is 0.5, or 0.7, or anywhere else on that spectrum, so manufacturers have stuck to using the VA rating out of tradition and an abundance of caution. We asked Tim Derochie at CyberPower about the topic, and he let out a knowing chuckle before we even finished the question. Nobody particularly cares for this bit of confusion, but it probably isn’t going anywhere.
In a UPS, most people want only backup power during a power outage, so we looked at basic UPS models that offer simple protection at an affordable price. If you have more-complex needs or a bigger budget, you can find additional options to choose from, including extendable battery capacity, more-compact lithium-ion batteries, and pure-sine-wave power.
Compared with the sealed lead-acid batteries (similar to a car battery) that most UPS manufacturers use, lithium-based batteries (like that of a laptop) can provide much more energy from a much smaller mass and, in many applications, can last years longer. However, those benefits are currently outweighed by per-minute run-time costs that are almost twice as high, and UPS manufacturers are just starting to experiment with them.
APC markets the compact BGE50ML specifically for keeping home networks running. It’s about half the size of our home-networking picks above, but APC’s claim of over two hours of run time is based on a 10 W load—we had a hard time finding a common network configuration that would use so little power. Although your gear may not run at its maximum load all the time, 50 W is a more common load for a home modem and router; with that load the BGE50ML is rated for only about 30 minutes. The model’s other premium feature is a removable USB battery pack that you can use to power a tablet or smartphone on the go. For the same amount of money, however, you could get more value with our CyberPower home-network UPS pick and one or more of our USB battery pack picks to take with you when you need a portable battery.
A few Wirecutter editors recently picked up APC’s more reasonably priced BGE90M, which is similarly aimed at low-power network devices but lacks the removable USB battery. In one editor’s real-world power outage, the BGE90M kept a router and modem going for almost an hour. But with only three ungrounded outlets and not even a token amount of surge protection, it doesn’t have the broad appeal that our picks do—though the price is tempting, since frequent sales bring the expected run-time value down to less than a dollar per minute. The BGE50ML and BGE90M might not be top picks yet, but as the cost of lithium batteries continues to drop and these compact units become the norm, we may consider them again for niche applications.
While the move to lithium-based batteries may still be a ways off, the current trend in UPS products is making pure-sine-wave inverters the norm. Batteries store and release power as direct current (DC), but residential outlets use alternating current (AC). Whereas DC power shoots through electrical wires, AC flows like waves, oscillating up and down. To turn DC power into AC power, you need an inverter that makes those waves. Manufacturers market the cheapest inverter option as a modified-sine-wave inverter, but it would be more aptly called a stepped-approximation (or square-wave) inverter. Instead of making a true wave, it steps the power up and down quickly. For many electronics, this approach is okay, if a bit inefficient. But for some devices, square waves can cause problems, from buzzing you can hear with audio equipment to flickers in tube-based displays to melting plastics and mystery smoke. Perhaps counterintuitively, expensive electronics such as laptops are often fine with such inverters thanks to more-refined power supplies that can better handle subpar power. A CyberPower representative told us that the company can never predict which products will have problems, but for mission-critical gear or for gaming rigs that tend to be finicky about power supplies, the representative recommended stepping up to CyberPower’s PFC Sinewave series of UPS models. APC and other manufacturers are offering more pure-sine-wave options, as well.