GSMArena team, 20 February 2019

Xiaomi Mi 9 review

3. Display, battery life, speaker, audio

Display

The Xiaomi Mi 9 packs a 6.39" Super AMOLED screen of 1080p resolution with a waterdrop-like notch. The panel has a resolution of 1,080 x 2,340 pixels that makes up for a very decent density at 402ppi. It is also one of the tallest screens around with an aspect ratio of 19.5:9. That's not the highest number of pixels we've enjoyed but the display looks great and its punchiness makes every picture spring to life.

The display is protected by the latest Gorilla Glass 6 by Corning - the most shatter-resistant glass in the smartphone world. We are yet to see how it will pass the test of time, but seeing already other GG6-featuring phones, it is indeed doing great in drops, although it's rather prone to scratches.

The screen has a very decent brightness for an OLED panel of 430 nits - exactly what Xiaomi promises. But it can go as high as 620 nits in bright light if you leave it on Auto.

Display test	100% brightness
Display test	Black, cd/m²	White, cd/m²	Contrast ratio
Xiaomi Mi 9	0	428	∞
Xiaomi Mi 9 (Max Auto)	0	620	∞
Xiaomi Mi 8	0	458	∞
Xiaomi Mi 8 (Max Auto)	0.002	624	312000
Xiaomi Mi Mix 3	0	445	∞
Xiaomi Mi Mix 3 (Max Auto)	0	633	∞
Samsung Galaxy Note9	0	367	∞
Samsung Galaxy Note9 (Max Auto)	0	658	∞
Oppo RX17 Pro	0	455	∞
Honor Magic 2	0	433	∞
Huawei Mate 20	0.347	491	1415
Huawei Mate 20 (Max Auto)	0.554	778	1404
Apple iPhone XS	0	660	∞
LG V40 ThinQ	0.002	323	161500
LG V40 ThinQ (Max Auto)	0.008	638	79750

The sunlight contrast on the Xiaomi Mi 9 is excellent, and we expect nothing less from an AMOLED screen of that brightness.

Sunlight contrast ratio

Apple iPhone XS
5.171
Apple iPhone X
5.013
Huawei Mate 20 Pro
4.965
OnePlus 5T
4.789
Samsung Galaxy S8
4.768
Asus ROG Phone
4.765
Samsung Galaxy S8+
4.658
Samsung Galaxy S9
4.63
Samsung Galaxy S6 edge+
4.615
Samsung Galaxy S9+
4.537
Samsung Galaxy Note9
4.531
Apple iPhone XS Max
4.516
Sony Xperia XZ3
4.502
Motorola Moto Z2 Play
4.459
Oppo R11
4.454
Samsung Galaxy S7 edge
4.439
Oppo RX17 Pro
4.434
OnePlus 3
4.424
Samsung Galaxy S7
4.376
Google Pixel 3
4.35
Huawei Mate 20 X
4.337
Samsung Galaxy A7 (2018)
4.324
OnePlus 6
4.321
Xiaomi Mi Mix 3
4.291
vivo NEX Dual Display (second display)
4.289
HTC One A9
4.274
LG V40 ThinQ
4.256
Oppo R15 Pro
4.251
Samsung Galaxy Note7
4.247
Samsung Galaxy A3
4.241
Nokia 8
4.239
Google Pixel 2 XL (pre-update)
4.234
OnePlus 3T
4.232
Samsung Galaxy A9 (2018)
4.22
Google Pixel XL
4.164
ZTE Axon 7
4.154
Samsung Galaxy Note8
4.148
Meizu Pro 7 Plus
4.147
OnePlus 6T
4.138
Samsung Galaxy S6 edge
4.124
Samsung Galaxy A7 (2017)
4.124
vivo V11
4.113
vivo NEX Dual Display
4.108
Huawei Mate 10 Pro (normal)
4.096
Samsung Galaxy Note5
4.09
Huawei P20 Pro
4.087
Xiaomi Mi 8
4.086
Meizu 15
4.082
Nokia 6 (2018)
4.052
Google Pixel 2 (pre-update)
4.023
LG V30
4.022
Huawei Nexus 6P
4.019
vivo NEX S
4.012
Honor Magic 2
4.01
Samsung Galaxy J7 Pro
3.998
OnePlus X
3.983
Vivo Xplay5 Elite
3.983
LG G7 ThinQ (outdoor)
3.978
Oppo R7s
3.964
Apple iPhone 7
3.964
Apple iPhone 8 (True Tone)
3.957
Huawei P9 Plus
3.956
Oppo Find X
3.954
Meizu Pro 6 Plus
3.935
Lenovo Moto Z
3.931
Xiaomi Mi 9
3.921
Samsung Galaxy A7 (2016)
3.918
OnePlus 5
3.914
Samsung Galaxy C5
3.911
Xiaomi Mi 8 SE
3.901
Samsung Galaxy C7
3.896
Samsung Galaxy A5
3.895
Samsung Galaxy J7 outdoor
3.879
Samsung Galaxy J2 outdoor
3.873
Motorola Moto G6 Plus
3.865
Samsung Galaxy A8
3.859
Samsung Galaxy A8 (2018)
3.842
Apple iPhone 6
3.838
Microsoft Lumia 950XL
3.837
Samsung Galaxy A6+ (2018)
3.834
Sony Xperia XZs
3.818
Samsung Galaxy A9 (2016)
3.817
Motorola Moto X (2014)
3.816
Samsung Galaxy J7 (2017)
3.812
Samsung Galaxy A5 (2017)
3.804
Samsung Galaxy J7 (2016) outdoor mode
3.802
Xiaomi Redmi Pro
3.798
LG V20 Max auto
3.798
Sony Xperia XZ
3.795
Samsung Galaxy A5 (2016)
3.789
Apple iPhone 6s
3.783
Meizu Pro 5
3.781
Microsoft Lumia 650
3.772
Xiaomi Mi 6
3.767
Sony Xperia XZ1
3.765
Samsung Galaxy J7 (2016)
3.756
Nokia 8 Sirocco
3.745
Sony Xperia XZ1 Compact
3.729
Apple iPhone 8 Plus (True Tone)
3.725
Oppo F1 Plus
3.709
Vivo X5Pro
3.706
Sony Xperia X Compact
3.694
Samsung Galaxy A3 (2017)
3.688
Huawei P20
3.683
Apple iPhone SE
3.681
Huawei Mate 9
3.68
Samsung Galaxy A7
3.679
Sony Xperia XZ2 Compact
3.675
Meizu PRO 6
3.659
BlackBerry Priv
3.645
Sony Xperia XA1 Ultra
3.597
Huawei Honor View 20
3.597
Apple iPhone 7 Plus
3.588
Sony Xperia XZ2
3.58
LG G6
3.556
Samsung Galaxy S5
3.549
Apple iPhone 6s Plus
3.53
Motorola Moto Z Play
3.526
Samsung Galaxy J3 (2016)
3.523
Samsung Galaxy J3 (2016) outdoor mode
3.523
Acer Jade Primo
3.521
Microsoft Lumia 950
3.512
Oppo R7 Plus
3.499
Nokia 7 plus
3.479
nubia Z11
3.466
Huawei P10 Plus
3.456
HTC U Ultra
3.453
Motorola Moto G6
3.448
Sony Xperia XA2 Ultra
3.445
Sony Xperia XA2 Plus
3.445
Samsung Galaxy J7
3.422
Motorola Moto G6 Play
3.419
Meizu MX5
3.416
LG V20
3.402
Samsung Galaxy A6 (2018)
3.397
Xiaomi Redmi Note 5 AI Dual Camera
3.393
LG G7 ThinQ
3.39
Huawei P10
3.379
Samsung Galaxy J5 (2016)
3.378
Oppo R9s
3.352
Honor Play
3.349
Samsung Galaxy J2
3.235
Oppo Realme 2 Pro
3.235
Motorola Moto X Play
3.222
Oppo F3 Plus
3.218
BlackBerry KEY2
3.212
Huawei Mate 9 Pro
3.206
Huawei P9
3.195
Xiaomi Mi Mix 2
3.19
Motorola Moto G7 Play
3.18
Motorola Moto G7 Power
3.176
ZTE Nubia Z17
3.159
Oppo R11s
3.153
Lenovo Vibe Shot
3.113
Honor 8X
3.113
HTC U11 Life
3.108
Motorola Moto X Force
3.105
LG Nexus 5X
3.092
HTC U11
3.089
Xiaomi Mi A2 Lite
3.087
HTC U12+
3.085
Xiaomi Redmi S2 (Y2)
3.077
Huawei Mate S
3.073
Oppo F9
3.069
Huawei P Smart 2019
3.069
Xiaomi Mi Max 3
3.061
Xiaomi Pocophone F1
3.059
Huawei Mate 20
3.052
Huawei Mate 20 Lite
3.051
Motorola One (P30 Play)
3.026
Motorola Moto G7
3.011
Motorola Moto G7 Plus
3.01
Oppo Realme 2
3.006
Sony Xperia L1
2.994
Sony Xperia X
2.989
LG Q6
2.987
Huawei P10 Lite
2.974
Samsung Galaxy Note
2.97
Xiaomi Redmi Note 6 Pro
2.966
Huawei P20 Lite
2.952
Xiaomi Redmi 5
2.951
Huawei Mate 8
2.949
Sony Xperia XA2
2.938
Oppo Realme 1
2.932
Razer Phone 2
2.932
Xiaomi Redmi 4
2.92
Xiaomi Redmi 3S
2.913
Xiaomi Redmi 5 Plus
2.913
Sony Xperia XA Ultra
2.906
LG G5
2.905
Huawei Honor View 10
2.896
Xiaomi Redmi 3s Prime
2.893
Xiaomi Redmi Note 7
2.893
Xiaomi Mi 5s Plus
2.884
Sony Xperia XZ Premium (sRGB)
2.877
Sony Xperia XZ Premium
2.877
Sony Xperia Z5
2.876
Nokia 3
2.871
Sony Xperia XZ2 Premium
2.867
Nokia 3.1
2.837
Realme U1
2.815
Lenovo Moto M
2.813
Nokia 7.1
2.804
Xiaomi Redmi 3 Pro
2.803
Sony Xperia Z5 compact
2.784
Honor 10 (Vivid)
2.757
Nokia 2
2.752
Meizu MX6
2.751
LG V10
2.744
Huawei Mate 10 (normal)
2.742
Motorola Moto G5S Plus
2.737
Xiaomi Redmi 3
2.735
Huawei Honor 7X
2.734
Xiaomi Redmi Note 4 (S625)
2.714
Meizu M5
2.71
Xiaomi Mi A2
2.696
Xiaomi Mi A1
2.689
Sony Xperia Z3
2.618
Xiaomi Mi 5X (Standard)
2.616
Sony Xperia XA
2.609
Motorola Moto G4 Plus
2.582
Motorola Moto G4 Plus (max auto)
2.582
Meizu M5s
2.58
Xiaomi Mi 4c
2.574
LeEco Le Max 2
2.567
Microsoft Lumia 640
2.563
Asus Zenfone 3 ZE552KL
2.563
Huawei P Smart
2.563
Xiaomi Mi Max 2
2.561
HTC U11+
2.556
Xiaomi Redmi Note 5A (Y1)
2.556
Lenovo Moto G4
2.544
Lenovo K6 Note
2.544
Oppo F1
2.528
Sony Xperia Z5 Premium
2.525
Huawei Honor 7 Lite / Honor 5c
2.506
Sony Xperia M4 Aqua
2.503
Huawei Honor 10 Lite
2.497
Lenovo Vibe K5
2.459
Meizu m3 max
2.447
Xiaomi Mi 5X (Auto)
2.417
HTC 10 evo
2.407
Huawei Honor 7
2.406
Vivo V7
2.404
Sony Xperia E5
2.386
ZUK Z1 by Lenovo
2.382
HTC 10
2.378
Oppo F3
2.376
vivo V5 Plus
2.371
Meizu m1 note
2.362
Huawei nova plus
2.329
Razer Phone
2.328
Huawei P8
2.196
Meizu M5 Note
2.189
Huawei Honor 6
2.169
Xiaomi Redmi Note 2
2.166
OnePlus Two
2.165
HTC One X
2.158
LG Aka
2.145
Xiaomi Redmi Note 4 (X20)
2.145
Archos 50 Diamond
2.134
Xiaomi Redmi Note
2.119
Xiaomi Mi 4S
2.095
Acer Liquid X2
2.084
Huawei P8lite
2.078
vivo V5
2.059
Moto G 3rd gen max manual
2.026
Xiaomi Mi 3
2.001
Xiaomi Mi Max
1.996
Sony Xperia E4g
1.972
OnePlus One
1.961
Sony Xperia Z2
1.944

The screen supports the DCI-P3 color space and its color reproduction is extremely very accurate with an average deltaE of 1.5 and a maximum deviation of 3.1. These are the measurements we took in Standard Contrast mode.

If you leave it on Adaptive Contrast - it's on by default - the phone automatically adjusts colors based on the surrounding light so any measurements here would be irrelevant. Finally, the Increased Contrast mode makes for a more saturated look, mostly boosting greens and reds, but going a little easier on the blues.

Battery life

The Xiaomi Mi 9 is powered by a modest 3,300mAh battery - that's 100mAh less than the cell inside the Mi 8. The good news is the Mi 9 supports both wired and wireless fast charging. But here comes the tricky part.

The Mi 9 ships with an 18W charger within its box and by all means - it's doing a decent job with the 3,300 mAh battery. It can take a depleted battery to 45% in half an hour. But if that's not enough for you, for some extra $20 you can get yourself an even faster charger.

The Mi 9 supports 20W wireless and 27W wired charging called Charge Turbo. You can get both those goodies as part of the Xiaomi Mi 9 wireless charger bundle. You can't buy those pieces separately, but at that price, we'd say that's pretty understandable.

So, if you obtain this optional accessory and use the 27W charger inside its box, then you will charge your Mi 9 up to 70% in just 30 mins. It takes only 65 minutes to fully charge the Mi 9 with this adapter.

The wireless charger part of this bundle features a nice soft finish and is very lightweight. It's worth noting, that when using it, you can almost hear a slight hums during use because there is a small fan to cool the thing. We managed to charge the Mi 9 up to 30% in 30 minutes with this mat, not impressive and nowhere near the 45% we got with the 18W wired charger. Maybe it depends on the room and battery temp, but still, the quoted power output of 20W seems rather far-fetched.

And now, let's see how the Xiaomi Mi 9 and it's Snapdragon 855 chip did in our battery test.

Update, Mar 1: We've retested the Xiaomi Mi 9 after we found some issues with the original test data. The scoresheet and the test description below has been updated to reflect the changes. In short - the video test result went down, the web browsing test went up and the standby went a bit higher up, too. The end result is a slightly higher Endurance rating from 91h to 95h.

The Mi 9 posted an excellent endurance rating of 95 hours and great scores across the board. The screen-on-times are great - you can use it for 12 hours of web browsing and 16 hours of video playback.

The standby has improved noticeably since the Snapdragon 845 chipset and that helped the Mi 9 outscore the Mi 8 in this respect.

Our battery tests were automated thanks to SmartViser, using its viSer App. The endurance rating above denotes how long a single battery charge will last you if you use the Xiaomi Mi 9 for an hour each of telephony, web browsing, and video playback daily. We've established this usage pattern so that our battery results are comparable across devices in the most common day-to-day tasks. The battery testing procedure is described in detail in case you're interested in the nitty-gritty. You can check out our complete battery test table, where you can see how all of the smartphones we've tested will compare under your own typical use.

Loudspeaker

A lot of things have changed since the Mi 8, but the loudspeaker is not one of them. We were disappointed to find out that the Mi 9 doesn't boast stereo speakers. Instead, it has the same bottom-firing loudspeaker as the Mi 8 and it even scored the same Very Good mark at our loudness test.

It does sound very well with clean output and rich tones, though.

Speakerphone test	Voice, dB	Pink noise/ Music, dB	Ringing phone, dB	Overall score
Xiaomi Mi Mix 3	67.9	71.6	73.7	Good
Xiaomi Mi 8	68.1	72.3	82.2	Very Good
OnePlus 6T	67.2	72.5	84.5	Very Good
Xiaomi Mi 9	70.1	74.2	81.6	Very Good
Apple iPhone XS	71.5	75.7	78.9	Very Good
Samsung Galaxy Note9	71.2	74.9	80.2	Very Good
Xiaomi Mi 8 SE	70.5	74.1	85.2	Excellent
Honor Magic 2	72.5	73.6	85.2	Excellent
Xiaomi Redmi Note 7	69.8	71.5	90.5	Excellent
Huawei Mate 20 X	71.4	73.5	91.1	Excellent
LG G7 ThinQ	78.3	76.4	82.3	Excellent

Audio quality

Xiaomi Mi 9 did well with an active external amplifier, delivering an output of above average loudness and flawless clarity.

It handled headphones well with a contained hike in stereo crosstalk the only notable change. Loudness remained above average too, adding up to a solid, if not quite spectacular performance.

Test	Frequency response	Noise level	Dynamic range	THD	IMD + Noise	Stereo crosstalk
Xiaomi Mi 9	+0.02, -0.01	-93.9	93.1	0.0015	0.0066	-91.9
Xiaomi Mi 9 (headphones)	+0.05, -0.04	-92.6	93.5	0.0026	0.072	-58.7
Xiaomi Mi Mix 3	+0.02, -0.02	-93.2	93.2	0.0014	0.072	-90.6
Xiaomi Mi Mix 3 (headphones)	+0.09, -0.07	-92.7	92.6	0.0033	0.151	-60.9
Huawei Mate 20	+0.02, -0.16	-92.1	92.0	0.0017	0.013	-85.6
Huawei Mate 20 (headphones)	+0.07, -0.07	-92.1	92.4	0.0021	0.106	-66.5
Samsung Galaxy Note9	+0.01, -0.03	-93.7	93.7	0.0017	0.0074	-94.1
Samsung Galaxy Note9 (headphones)	+0.03, -0.02	-93.6	93.5	0.0033	0.046	-93.2

Xiaomi Mi 9 frequency response

You can learn more about the tested parameters and the whole testing process here.

Next Page » 4. Software

3. Display, battery life, speaker, audio

Reviews Xiaomi Mi 9 reviewPage 3