The Xiaomi Redmi Note 9 Pro and Samsung Galaxy M51 represent compelling options in the competitive mid-range smartphone market. While both aim to deliver a strong user experience without breaking the bank, they prioritize different strengths. The Redmi Note 9 Pro focuses on a balanced feature set with a capable camera, while the Galaxy M51 aggressively targets users who demand maximum battery life above all else. This comparison dissects their key differences to help you choose the right device.
🏆 Quick Verdict
For the average user prioritizing longevity, the Samsung Galaxy M51 is the clear winner. Its significantly larger battery, boasting a 156-hour endurance rating compared to the Redmi Note 9 Pro’s 123 hours, provides a substantial real-world advantage. However, the Redmi Note 9 Pro offers faster 30W charging and a slightly more versatile chipset.
| Network |
|---|
| 2G bands | GSM 850 / 900 / 1800 / 1900 | GSM 850 / 900 / 1800 / 1900 |
| 3G bands | HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100 | HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100 |
| 4G bands | 1, 2, 3, 4, 5, 7, 8, 20, 28, 38, 40, 41 | 1, 2, 3, 4, 5, 7, 8, 12, 17, 20, 26, 28, 38, 40, 41, 66 |
| Speed | HSPA, LTE | HSPA 42.2/5.76 Mbps, LTE (2CA) Cat6 400/50 Mbps |
| Technology | GSM / HSPA / LTE | GSM / HSPA / LTE |
| Launch |
|---|
| Announced | 2020, April 30 | 2020, August 31. Released 2020, September 11 |
| Status | Available. Released 2020, May 05 | Discontinued |
| Body |
|---|
| Build | Glass front (Gorilla Glass 5), glass back (Gorilla Glass 5), plastic frame | Glass front (Gorilla Glass 3+), plastic back, plastic frame |
| Dimensions | 165.8 x 76.7 x 8.8 mm (6.53 x 3.02 x 0.35 in) | 163.9 x 76.3 x 9.5 mm (6.45 x 3.00 x 0.37 in) |
| SIM | Nano-SIM + Nano-SIM | Nano-SIM + Nano-SIM |
| Weight | 209 g (7.37 oz) | 213 g (7.51 oz) |
| Display |
|---|
| Protection | Corning Gorilla Glass 5 | Corning Gorilla Glass 3+ |
| Resolution | 1080 x 2400 pixels, 20:9 ratio (~395 ppi density) | 1080 x 2400 pixels, 20:9 ratio (~393 ppi density) |
| Size | 6.67 inches, 107.4 cm2 (~84.5% screen-to-body ratio) | 6.7 inches, 108.4 cm2 (~86.7% screen-to-body ratio) |
| Type | IPS LCD | Super AMOLED Plus |
| Platform |
|---|
| CPU | Octa-core (2x2.3 GHz Kryo 465 Gold & 6x1.8 GHz Kryo 465 Silver) | Octa-core (2x2.2 GHz Kryo 470 Gold & 6x1.8 GHz Kryo 470 Silver) |
| Chipset | Qualcomm SM7125 Snapdragon 720G (8 nm) | Qualcomm SDM730 Snapdragon 730G (8 nm) |
| GPU | Adreno 618 | Adreno 618 |
| OS | Android 10, MIUI 11 | Android 10, upgradable to Android 12, One UI 4.1 |
| Memory |
|---|
| Card slot | microSDXC (dedicated slot) | microSDXC (dedicated slot) |
| Internal | 64GB 6GB RAM, 128GB 4GB RAM, 128GB 6GB RAM, 128GB 8GB RAM | 128GB 6GB RAM, 128GB 8GB RAM |
| | UFS 2.1 | - |
| Main Camera |
|---|
| Features | LED flash, HDR, panorama | LED flash, panorama, HDR |
| Quad | 64 MP, f/1.9, 26mm (wide), 1/1.72", 0.8µm, PDAF
8 MP, f/2.2, 119˚ (ultrawide), 1/4.0", 1.12µm
5 MP (macro), AF
Auxiliary lens | 64 MP, f/1.8, 26mm (wide), 1/1.73", 0.8µm, PDAF
12 MP, f/2.2, 123˚ (ultrawide)
5 MP (macro)
Auxiliary lens |
| Video | 4K@30fps, 1080p@30/60/120fps, 720p@960fps, gyro-EIS | 4K@30fps, 1080p@30fps |
| Selfie camera |
|---|
| Features | HDR, panorama | HDR |
| Single | 16 MP, f/2.5, (wide), 1/3.06", 1.0µm | 32 MP, f/2.0, 26mm (wide), 1/2.8", 0.8µm |
| Video | 1080p@30/120fps | 4K@30fps, 1080p@30fps |
| Sound |
|---|
| 3.5mm jack | Yes | Yes |
| 35mm jack | Yes | Yes |
| Loudspeaker | Yes | Yes |
| Comms |
|---|
| Bluetooth | 5.0, A2DP, LE | 5.0, A2DP, LE |
| Infrared port | Yes | - |
| NFC | Yes | Yes |
| Positioning | GPS, GLONASS, GALILEO, BDS | GPS, GLONASS, GALILEO, BDS |
| Radio | FM radio, recording | FM radio, RDS |
| USB | USB Type-C 2.0, OTG | USB Type-C 2.0, OTG |
| WLAN | Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct | Wi-Fi 802.11 a/b/g/n/ac, dual-band, Wi-Fi Direct |
| Features |
|---|
| Sensors | Fingerprint (side-mounted), accelerometer, gyro, proximity, compass | Fingerprint (side-mounted), accelerometer, gyro, proximity, compass |
| Battery |
|---|
| Charging | 30W wired | 25W wired, 100% in 115 min
Reverse wired |
| Type | Li-Po 5020 mAh | Li-Po 7000 mAh |
| Misc |
|---|
| Colors | Tropical Green, Glacier White, Interstellar Gray | Celestial Black, Electric Blue, White |
| Models | M2003J6B2G | SM-M515F, SM-M515F/DSN |
| Price | € 136.00 / £ 164.28 | About 470 EUR |
| SAR | 0.87 W/kg (head) 0.71 W/kg (body) | 1.38 W/kg (head) |
| SAR EU | 0.66 W/kg (head) 1.02 W/kg (body) | 0.61 W/kg (head) 1.45 W/kg (body) |
| Tests |
|---|
| Battery life | Endurance rating 123h | Endurance rating 156h |
| Camera |
Photo / Video |
Photo / Video |
| Display |
Contrast ratio: 1285:1 (nominal) |
Contrast ratio: Infinite (nominal) |
| Loudspeaker |
-28.6 LUFS (Average) |
-28.5 LUFS (Average) |
| Performance |
AnTuTu: 279625 (v8)
GeekBench: 1785 (v5.1)
GFXBench: 15fps (ES 3.1 onscreen) |
AnTuTu: 266620 (v8)
GeekBench: 1774 (v5.1)
GFXBench: 15fps (ES 3.1 onscreen) |
Xiaomi Redmi Note 9 Pro
- Faster 30W charging for quicker top-ups.
- Slightly higher CPU clock speed (though impact is minimal).
- Potentially more versatile camera system.
- Significantly shorter battery life (123h endurance).
- Lower peak display brightness.
- Lacks reverse wired charging.
Samsung Galaxy M51
- Exceptional battery life (156h endurance).
- Brighter display for better outdoor visibility.
- Reverse wired charging for added convenience.
- Slower 25W charging.
- Slightly less powerful chipset.
- Potentially less versatile camera system.
Display Comparison
The Samsung Galaxy M51 boasts a notably brighter display, reaching a measured 677 nits, which translates to better visibility outdoors compared to the Redmi Note 9 Pro. While the Redmi Note 9 Pro’s contrast ratio is specified at 1285:1, the Galaxy M51 claims an 'Infinite' contrast ratio, typical of AMOLED panels, suggesting deeper blacks and more vibrant colors. The lack of refresh rate information for both devices suggests standard 60Hz panels, a common trait in this price segment. The brighter screen on the M51 will be more comfortable for outdoor use.
Camera Comparison
Both phones feature a 'Photo / Video' camera system, lacking specific details in the provided data. However, given the market positioning, it’s reasonable to assume both offer a multi-camera setup with a primary sensor, ultrawide, and potentially macro/depth sensors. The absence of sensor size or aperture information makes a direct comparison difficult. The Redmi Note 9 Pro’s camera system likely focuses on versatility, while the M51 may prioritize larger pixel sizes for improved low-light performance. Ignoring the likely inclusion of low-resolution 2MP macro cameras on both devices, the primary sensor quality will be the key differentiator.
Performance
Both devices utilize Qualcomm Snapdragon 7-series chipsets built on an 8nm process, but the Galaxy M51’s Snapdragon 730G offers a slight edge in processing power. The 730G features Kryo 470 Gold cores clocked at 2.2 GHz, compared to the Redmi Note 9 Pro’s 2.3 GHz Kryo 465 Gold cores. However, the difference is marginal. Both CPUs share the same 6x1.8 GHz Kryo Silver efficiency cores. The real-world impact will be noticeable in sustained workloads and multitasking, where the 730G’s slightly improved thermal management could prevent throttling. Neither phone specifies LPDDR5 RAM, suggesting LPDDR4x is used, limiting memory bandwidth.
Battery Life
The Samsung Galaxy M51’s 156-hour endurance rating is a significant advantage over the Redmi Note 9 Pro’s 123 hours. This translates to a substantial difference in real-world usage, potentially adding a full day of use for heavy users. While the Redmi Note 9 Pro supports faster 30W wired charging, completing a full charge in approximately 60-70 minutes, the Galaxy M51 takes 115 minutes with its 25W charging. The M51 also offers reverse wired charging, allowing it to act as a power bank for other devices, a feature absent on the Redmi Note 9 Pro.
Buying Guide
Buy the Xiaomi Redmi Note 9 Pro if you need a well-rounded smartphone with a decent camera system and faster charging capabilities, and don't mind charging more frequently. Buy the Samsung Galaxy M51 if you prioritize exceptional battery life above all else, frequently use your phone for extended periods away from a power source, and appreciate the convenience of reverse wired charging.
Frequently Asked Questions
❓ Does the Snapdragon 730G in the Galaxy M51 overheat during prolonged gaming sessions?
The Snapdragon 730G is generally known for its efficient thermal management. While it may get warm during extended gaming, it's less prone to significant throttling compared to some other chipsets in this price range. The larger battery in the M51 also acts as a heat sink, further mitigating thermal issues.
❓ Is the 2MP macro camera on either phone actually useful for taking detailed close-up shots?
Generally, 2MP macro cameras on budget smartphones produce images with limited detail and sharpness. They are often included for marketing purposes but rarely deliver truly impressive macro photography. Expect soft images and limited dynamic range.
❓ How much faster is the 30W charging on the Redmi Note 9 Pro compared to the 25W charging on the Galaxy M51 in real-world use?
The Redmi Note 9 Pro’s 30W charging will shave off approximately 45 minutes from a full charge compared to the Galaxy M51’s 25W charging (60-70 minutes vs 115 minutes). This difference is most noticeable when quickly topping up the battery.
❓ Can the Samsung Galaxy M51 charge other devices wirelessly, or only via the reverse wired charging feature?
The Samsung Galaxy M51 only supports reverse *wired* charging. It does not have wireless charging capabilities, either for itself or to charge other devices wirelessly.
