OnePlus 9 review

Display

The OnePlus 9 has a 6.55-inch, 2400x1800 resolution, 8-bit AMOLED display. The display has a 120Hz variable refresh rate and is capable of displaying HDR content. All of these specs are identical to the OnePlus 8T since it's using the same display.

In color performance, the OnePlus 9 display performed exceptionally well, with an average deltaE 2000 figure of around 1.7 in both sRGB and Display-P3 testing. The display can also achieve near 100% coverage of both spectrums.

OnePlus provides a manual toggle in the settings to switch between the more accurate sRGB (Natural) mode or the more vivid Display-P3 (Vivid) mode. While the choice is entirely up to you, we think the Natural mode is the way to go as the device can automatically switch to P3 in applications that support it thanks to built-in color management in Android.

Like the OnePlus 9 Pro, the OnePlus 9 supports refresh rates up to 120Hz and can ramp down to lower values to save power. However, since this isn't an LTPO display, it can't go down to the claimed 1Hz that the OnePlus 9 Pro display supposedly can.

The default behavior for the display while interacting with it is to refresh at 120Hz. When the user stops interacting, the refresh rate drops down to a lower value of 60Hz for brightness values above 50% and 90Hz for brightness values below 50%. On top of that, certain apps and activities can cause the display to lock itself to 60Hz. This includes apps like Camera, Google Maps, etc., activities such as watching a fullscreen video and playing most games. The display will also drop the refresh rate of the app from 120Hz to 60Hz if the app has an embedded map or camera view for that particular screen.

As with the OnePlus 9 Pro, we would have liked to see the OnePlus 9 display support more intermediate values apart from 120Hz, 90Hz, and 60Hz. A 24/48Hz mode for watching 24fps content would have been great.

Perhaps more frustrating is OnePlus' continued lack of support for high refresh rate gaming. The company has whitelisted a very small number of games, such as Fortnite, PUBG Mobile, Pokemon Go, etc., and these are the only titles allowed to run at a maximum of 90Hz. This leaves a vast majority of games unsupported and there are also no titles that run above 90Hz. Moreover, OnePlus will also drop down the refresh rate of the display from 90Hz to 60Hz in supported games when the player stops interacting, which causes a jarring drop in fluidity because, unlike static UI screens, games tend to have moving elements on-screen animating at the display's refresh rate.

Like the OnePlus 9 Pro and the OnePlus 8 Pro, the OnePlus 9 has the Vibrant Color Effect Pro mode, which is intended to make videos appear more saturated. However, as with the OnePlus 9 Pro, the feature seems to do absolutely nothing on the OnePlus 9. On the OnePlus 8 Pro, enabling it would make all supported video apps appear strongly saturated. On the OnePlus 9, none of the apps we tried had any difference at all when the feature was enabled. We had first observed this on the OnePlus 8T and we are not quite sure what purpose this feature serves anymore.

There's also a new Ultra-high video resolution mode, which at the time of testing was only available for Instagram. This feature uses AI to add edge enhancement to videos within supported apps. Videos on Instagram had more pronounced detail but it does tend to look a bit artificial.

The OnePlus 9 does not support Hyper Touch and Motion graphics smoothing modes that the 9 pro has, which is fine as the former does not make much of a difference and the latter actively makes things look worse.

The OnePlus 9 has good HDR performance. While watching HDR10 content on YouTube and Netflix apps, we observed impressive peak brightness and vibrant colors. The display on the OnePlus 9 is only 8-bit, which doesn't quite allow the 10-bit colors in native HDR content to come through quite well but in most content this isn't easily noticeable, especially considering the small size of the display.

The OnePlus 9 display also has some glow when displaying blacks. This means, if the screen is meant to be perfectly black while playing back HDR content, the screen will appear like it's still on and displaying a dark shade of gray rather than be completely off. It's not clear what causes this and why it's only limited to the HDR mode but it's not something to worry about as it's only visible in a pitch dark room while watching content with a lot of deep blacks in it.

The display includes an optical fingerprint sensor. The fingerprint sensor on the OnePlus 9 is located unusually low, wherein it's only a few pixels above the navigation bar at the bottom.

As for the sensor performance, it's mostly fine. If you use the same finger every time to unlock then it will work without any hassles and almost instantly. However, OnePlus phones do tend to get bamboozled if you switch your fingers every once in a while, even if the other finger is also registered. But that's an issue that only crops up after you've used the phones for a while and not something that usually shows up during the review period.

Battery Life

The OnePlus 9 uses dual 2,250 mAh cells that equate to a total battery capacity of 4,500 mAh: roughly the same capacity as the OnePlus 8T. Despite the Qualcomm Snapdragon 888 platform's advertised boost in efficiency, the OnePlus 9's battery performance was only average.

The OnePlus 9 tested for over 28h in talk time and surpassed 13 hours of the web test. It also scored more than 15 hours on the video playback test. Despite the phone's decent test scores, the Snapdragon 888's higher standby power draw hindered the OnePlus 9 from a better score. The OnePlus 9 weighed in at an 87h rating overall. Other contenders powered by the Snapdragon 888 like the Xiaomi MI 11 and Oppo's Find X3 Pro also had similar endurance scores attributed to high standby draw.

The OnePlus 8T fared better just six months ago with similar call, web, and video scores equipped with identical battery capacity. The Snapdragon 888 didn't do as well as the 865 in our standby tests. Perhaps these can be addressed as OEMs continue to optimize their devices in future OTA updates.

Our battery tests were automated thanks to SmartViser, using its viSerDevice app. The endurance rating denotes how long the battery charge will last you if you use the device for an hour of telephony, web browsing, and video playback daily. More details can be found here.

All test results shown are achieved under the highest screen refresh rate mode. You can adjust the endurance rating formula manually so it matches better your own usage in our all-time battery test results chart where you can also find all phones we've tested.

Charging

The 4,500 mAh battery on the 8T, 9, and 9 Pro all use identical dual-cell battery tech. This means that the adapter is simultaneously fast-charging two batteries that work as one. OnePlus debuted 65W charging with the OnePlus 8T, but the 9 and 9 Pro get a bump up in charging speed with Warp Charge 65T. Both phones received improvement that "reduces internal charging resistance" so the battery can accept peak wattage for longer times before dialing down.

30min charging test (from 0%)

• OnePlus 9
  100%
• Oppo Find X3 Pro
  100%
• OnePlus 9 Pro
  99%
• OnePlus 8T
  94%
• Huawei Mate 40 Pro (66W bundled)
  87%
• Xiaomi Mi 11
  83%
• OnePlus 8
  69%
• OnePlus 8 Pro
  63%
• Apple iPhone 12 Pro
  59%
• Apple iPhone 12
  58%
• Apple iPhone 12 Pro Max
  55%
• Samsung Galaxy S21 Ultra 5G
  54%
• Samsung Galaxy S21+ 5G
  54%
• OnePlus 8 Pro (Warp Charge Wireless)
  48%
• Google Pixel 5
  41%
• Huawei Mate 40 Pro (65W PD)
  33%

Time to full charge (from 0%)

• Oppo Find X3 Pro
  0:28h
• OnePlus 9
  0:29h
• OnePlus 9 Pro
  0:32h
• OnePlus 8T
  0:36h
• Huawei Mate 40 Pro (66W bundled)
  0:45h
• Xiaomi Mi 11
  0:50h
• OnePlus 8
  0:53h
• Samsung Galaxy S21 Ultra 5G
  1:11h
• Samsung Galaxy S21+ 5G
  1:12h
• Apple iPhone 12
  1:30h
• Apple iPhone 12 Pro
  1:30h
• Apple iPhone 12 Pro Max
  1:32h
• Huawei Mate 40 Pro (65W PD)
  1:42h
• Google Pixel 5
  1:54h

With Warp Charge 65T, the 9's battery was fully replenished in 29 minutes, just as OnePlus promised. This is a full 10-minutes faster than the OnePlus 8's 39-minute full charge. The included Warp charger can be used to charge non-OnePlus devices at a maximum of 45W if they support USB PD or PPS.

Although the OnePlus 9 Pro supports the new Warp Charge 50 Wireless charger, this isn't the case with the 9. The non-Pro model gets support for 15W fast wireless charging and reverse wireless charging at up to 5W. Wireless charging is equipped on the OnePlus 9 - but only in North American and European variants.

Speaker test

The OnePlus 9 has a stereo speaker setup with a dedicated loudspeaker on the bottom of the phone and the earpiece serving as the second channel. In portrait, the earpiece get the left channel, while in landscape the phone uses the accelerometer to switch the channels to match the orientation.

A 'Very Good' rating is what the OnePlus 9 got for loudness in our test, essentially the same result as the OnePlus 9 Pro even though the numbers are marginally different.

Use the Playback controls to listen to the phone sample recordings (best use headphones). We measure the average loudness of the speakers in LUFS. A lower absolute value means a louder sound. A look at the frequency response chart will tell you how far off the ideal "0db" flat line is the reproduction of the bass, treble, and mid frequencies. You can add more phones to compare how they differ. The scores and ratings are not comparable with our older loudspeaker test. Learn more about how we test here.