When shopping for a new monitor, you’ll see a lot of familiar specifications, like 4K, 1440p or 1080p resolutions and refresh rates anywhere from 60Hz to 1,000Hz. You’ll rarely run into a monitor that doesn’t deliver on those specifications. However, there’s a whole host of other specifications that you may or may not be familiar with — color gamut, brightness, contrast and color accuracy — that play just as big a role in the quality of your experience. After running hundreds of tests on almost two dozen portable monitors, the evidence is clear: Many portable displays fail to meet all of their advertised specifications.
- More than half of the monitors tested failed to meet their advertised brightness by an average deficit of 15%.
- Most manufacturers are inaccurately representing contrast, with some boldly pronouncing absurdly high figures and a surprising number underestimating their contrast.
- The promise of a wide DCI-P3 color gamut coverage, which offers deeper reds, greens and blues, is rare, but often met.
- Most of the monitors that lived up to their stated specifications are the ones that made the fewest claims to begin with.
- The brightest portable monitor we tested was also one of the furthest from meeting its specified brightness, contrast and color gamut
I have tested a ton of displays over the years, from home theater projectors to desktop monitors and portable monitors. They all understandably use key specs to stand out and market themselves against the competition, so that potential buyers know the monitor will meet their needs.
While plenty of devices live up to their stated specifications, especially in the higher-end categories that tend to face far more scrutiny, the portable monitor market is awash in lower-end products with bold performance claims, many from brands you’ve probably never heard of. As a reviewer, I don’t take brands at their word if I can test the products for accuracy. Having gone hands-on with quite a few portable monitors and run hundreds of tests on them, it’s clear that this category isn’t one to dive into mindlessly or with a trusting heart.
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I compiled data from hundreds of assessments conducted on portable monitors I’ve tested, along with the advertised performance specifications, to see how often, and by how much, the monitors miss their mark.
Brightness is oft advertised and oft blundered
Not every monitor advertises every spec, but they all advertise a maximum brightness level they can hit. Brightness is measured in nits, which is equal to one candela per square meter, and a candela is a unit of light intensity roughly equivalent to one candle. The level of brightness plays a huge role in the kinds of spaces where you can easily use a monitor.
In a dim room, just 150 nits would generally be fine, providing enough light for easy visibility. If you’re often working in bright rooms or near large windows, you’ll likely want 300 to 400 nits to tackle the light reflected by the monitor. Outdoors, brightness becomes even more important with 400 nits serving as the floor unless the display has a really strong antireflective coating.
Getting a bright monitor doesn’t limit your ability to use it in other environments, since you can generally turn the brightness down. Many portable monitors target indoor use, producing fairly tame levels between 250 and 300 nits, while others offer loftier goals of 500 or even 1,200 nits to hold up outdoors. Most of those I’ve tested fail to hit this easily measured feature.
I tested 23 different monitors, and only 10 reached the advertised brightness. A good few of those even proved to be overachievers, running 16.29% brighter than they were rated to on average. The UPerfect GR19BU, MSI Pro MP156 E6 and UPerfect BE173BU were standouts, offering over 30% more brightness than specified.
On the flip side, the 13 monitors that underperformed had an average deficit of 15.67% relative to their advertised performance. It wasn’t just small-fry brands that failed, either. Asus, ViewSonic and Lenovo joined Innoview, UPerfect, KYY and Espresso in falling short.
It’s not as though the worst offenders are all awful, dim displays either. The Asus ZenScreen MQ149CD fell almost 25% short of its advertised brightness, but it was advertised at 500 nits, so it still delivered a pretty serviceable 379.2 nits.
Meanwhile, the brightest portable monitor I tested was also one of the farthest off the mark. The UPerfect BE16CU advertised 1,200 nits of brightness, but I measured it at just 890 nits. It was so far off that I did extensive retesting to make sure I wasn’t missing some setting that was holding it back. I even got in a second unit that managed to run brighter at 1,053 nits, but that’s still 12% short.
Advertised contrast ratios are also fairly meaningless
Many displays advertise their contrast ratio. Alongside brightness, it’s a pretty important detail because without contrast, there’d be nothing to see. It is, however, incredibly unreliable information to get from brands.
Most monitors I tested actually overdeliver. Thirteen outperformed their advertised specifications, and two that didn’t list a contrast ratio still performed better than I would have expected. The 13 monitors that outdid themselves did so by an average of 28.9%, which is a substantial amount to be off by.
The seven monitors that underperformed did so by an average of 16.7%. One monitor, the Acer PD163Q, really highlighted how off the marketing can be. It advertised a 100,000,000:1 contrast ratio. I measured it at 820:1 (and 1,110:1, since it actually has two displays). This gets to the matter of where brands are getting their data and in what test conditions. Perhaps the Acer PD163Q can deliver a white screen that’s 100 million times brighter than its darkest screen, but it can’t do so in normal operation with white-and-black boxes side by side.
Between the under- and overperformers, advertised contrast is basically worthless. Only seven of the monitors I tested were within 10% of their stated accuracy.
Color gamut promises are hit or miss, but the bolder claims tend to be met
The human eye can see a ton of color, but even the best monitors can display only some of this. Bad monitors shrink that down even further for what can be pretty bland, drab, lifeless color. If you want to avoid that latter experience, it’s worth knowing what to look for.
A monitor’s color gamut (the range of colors a display can show) or color coverage is listed as a percentage of some specific color space. Usually, you’ll see one or more of the following color spaces: sRGB, Rec. 709, DCI-P3 or just P3, BT.2020 or Rec. 2020, AdobeRGB and NTSC. These represent different ranges of color that are used by different groups and industries (such as sRGB for much of the web, Rec. 709 and NTSC for TV broadcasting, P3 and BT.2020 for cinema and AdobeRGB for print media and design).
If a display says it has 100% coverage of a color space, then it should be able to display every color within that space. Long story short, 100% sRGB is good, 100% P3/NSTC/AdobeRGB is great, 100% BT.2020 is amazing. It can get a little sticky when brands don’t specify whether they’re advertising “coverage” or “gamut” since a display can have a wide gamut that fails to actually cover a specific color space (e.g., a monitor with deep reds but weak greens and blues could have a gamut over 100% of the sRGB color space but might not have 100% coverage of that color space).
Often, monitors will advertise a color gamut, though not all do. Only 16 of the 23 explored here advertised a color gamut. Those that bothered were hit-or-miss on living up to the coverage.
Most just offered up an sRGB rating, as that’s a fairly common color space. Of the 12 that listed sRGB coverage, half delivered 100% coverage. A couple of them were only 1-2% off, which is excusable, but the Aura Triple Aero Pro Max achieved just 82% coverage despite promising 100% sRGB.
Two monitors listed their coverage only in NTSC terms (which I view as a warning flag, as it’s a good way to obscure poor sRGB coverage). The KYY K3 offered just 65% of the sRGB color space despite promising 72% NTSC gamut, which should have amounted to 100% sRGB coverage. Meanwhile, the Minisforum MDSA156 promised only 45% NTSC coverage, which is frankly awful, but it at least delivered on that promise.
Just five monitors swung for the fences with big DCI-P3 color gamuts. Interestingly, most walked the walk. The Asus ZenScreen MQ149CD, Monduo 14 Pro Duo, UPerfect BE173BU and UPerfect GR19BU all promised 100% DCI-P3 coverage and delivered it. The only outlier was the UPerfect BE16CU.
The UPerfect BE16CU is a curious case, because I tested two units with very different performance levels. UPerfect’s website didn’t mention P3 coverage, but the Amazon listing did. Oddly, the unit sent by UPerfect to me for testing almost met the grade, with 98% P3 coverage, which I would consider in range; the unit that shipped from Amazon only hit 81%.
My testing hasn’t revealed one monitor that’s better than all the others in every single way, but there is one that proved itself far and away the brightest: the UPerfect BE16CU. If you want a portable display that’s as bright as I’ve ever seen, this is the one, but I have a pile of caveats to share with you.
As mentioned before, the UPerfect BE16CU was also one of the monitors that fell furthest from its advertised performance. I had to get two separate units to figure out what was going on, and that only opened a bigger can of worms since the two monitors had very different performance characteristics.
Both monitors had decent contrast, but neither came close to what UPerfect claims. Both monitors had good color gamuts, but one was much dimmer, more colorful and had a very cold color temperature, while the other was the brightest, much less colorful, and had a comfortable color temperature. In other words, they were likely using entirely different panels. If I had gotten a third unit in for testing, who knows whether it would have performed like one of the first two or had yet more unique characteristics.
All of that said, both monitors were still the brightest I tested. That brightness also has a big asterisk: The UPerfect BE16CU requires auxiliary power to reach its peak brightness. It can run off a single USB-C connection to a laptop, but I only saw it hit 271 nits that way. If you want the full brightness on the go without connecting to a power adapter, you’ll need a power bank.
- Prioritizing baseline picture quality: Look for displays that have at least 300 nits, 95% sRGB coverage and a 1,000:1 contrast ratio in our testing.
- A great budget option: The Arzopa Z1RC remains a favorite for its respectable brightness (365.3 nits), color gamut (100% sRGB and 94% P3), contrast (1,080:1) and budget price ($124).
- Avoid if: Advertising that mentions 45% NTSC or below 70% sRGB is a recipe for a drab image with awful color. Even if you’re just looking at spreadsheets, the lack of color gamut can make your work more difficult without clear grid lines and colorization of cells.
Not everyone will need the ultimate, and there are plenty of good use cases that only call for a simple extra display. For example, if you want a second screen for email and chat while you work on your main display. In those cases, it makes sense to just look for one of the cheaper options you can find. Fortunately, there are some surprisingly good options that still come with low price tags.
If you’re shopping on a budget, you can still find monitors that perform well. A monitor that can hit 300 nits will generally be easy to see in most environments except in strong sunlight, especially if it has a matte finish. Anywhere above 95% sRGB coverage is decent and will give you a fair representation of what you’re looking at online while avoiding a drab look. A 1,000:1 contrast ratio also serves as a good baseline that should provide good legibility of details, so you’re not straining your eyes. These aren’t high bars to clear for a monitor, either. The Arzopa Z1RC delivers even more brightness and color gamut, and it packs a big and sharp display for around $124.
You should watch out for monitors that seem to promise too much or may use more obscure details. Generally, when I see a monitor advertising its color gamut in terms of NTSC coverage, it’s because it doesn’t do very well in the more commonly known sRGB color space. Many displays have 45% to 50% NTSC coverage, and they look bad. Unless your needs are a little beyond monochrome, you should probably avoid these.
Promises of extreme brightness often aren’t met, and even when they are, they’ll require extra power. In other words, don’t plan on getting 1,200 nits while you’re on the go without a big battery bank or running a cable to a power adapter. Finally, very few portable monitors deliver stunning contrast, so if you see something (other than an OLED panel) advertising anything beyond 2,000:1 contrast, look for a review that verifies that performance.
Now, with all this in mind, don’t feel the need to immediately write off any monitor that doesn’t meet its advertised performance levels. It feels like every other monitor I see is perfectly fine, but has some look-at-me spec that’s beyond what it’s capable of. You may get something that’s perfectly serviceable, but because of the advertising, you won’t be getting exactly what’s on the product page. As long as an underperforming monitor isn’t priced like an overperforming one, it can still provide a good value and decent quality. The Arzopa Z1RC, for instance, didn’t meet its advertised 1,200:1 contrast, but it’s still a great portable monitor and an excellent value.
When testing portable monitors, I make plenty of qualitative assessments: evaluations of the look and feel, eyeball tests of the splendor of the display or lack thereof, and the sticker shock of the price tag. Beyond that, I take quantitative measurements of their color gamut, brightness across different settings, contrast, white point, and CIE76 color accuracy using 48 color patches with a DataColor colorimeter.