BeastCompare

Asus Zenfone 4 Pro ZS551KL vs iPhone 18 Pro: Which One Should You Buy?

These two are too close to call on BeastScore — the right choice depends on what matters to you.

Head-to-head
Comparing 2 devicesSwipe ⇄
Asus

Asus Zenfone 4 Pro ZS551KL

Asus Zenfone 4 Pro ZS551KL
89/ 100
Launch pricePrice on request
Apple · 2026

iPhone 18 Pro

iPhone 18 Pro
89/ 100
Launch price$1,299
Head-to-head

Too close to call: 2 of 5 categories each

Here's exactly where each phone is stronger.

Asus Zenfone 4 Pro ZS551KL
Asus Zenfone 4 Pro ZS551KL
2 wins
iPhone 18 Pro
iPhone 18 Pro
2 wins
At a glance

Bigger shape = better phone.

SpeedCameraSelfieBatteryDisplay
Asus Zenfone 4 Pro ZS551KLiPhone 18 Pro
Category winners

Scores out of 100. "From specs" scores compare only the specs both phones list. How we score

  • Speedfrom specsiPhone 18 Pro
    60
    90
  • Camerafrom specsAsus Zenfone 4 Pro ZS551KL
    82
    80
  • VideoNot enough data
  • SelfieAsus Zenfone 4 Pro ZS551KL
    88
    76
  • Batteryfrom specsiPhone 18 Pro
    20
    43
  • Displayfrom specsTie
    88
    88
  • ConnectivityNot enough data
  • SecurityNot enough data
  • ValueNot enough data
Key differences
  • iPhone 18 Pro has the bigger battery4,288 mAh vs 3,600 mAh
  • Asus Zenfone 4 Pro ZS551KL has a sharper main camera50 MP vs 48 MP
  • iPhone 18 Pro has the bigger screen6.3" vs 5.5"
  • Asus Zenfone 4 Pro ZS551KL has a sharper selfie camera32 MP vs 18 MP
  • iPhone 18 Pro has more RAM12 GB vs 6 GB
  • iPhone 18 Pro can text for help by satelliteYes vs No
See all specs ↓

Why buy each phone

Swipe ⇄
Reasons to buy Asus Zenfone 4 Pro ZS551KL
  • ✓50 MP main camera
  • ✓5.5" display at 120 Hz
Reasons to buy iPhone 18 Pro
  • ✓Bigger 4,288 mAh battery (+688 mAh)
  • ✓48 MP main camera
  • ✓6.3" display at 120 Hz

Full specifications

Swipe ⇄
SpecificationAsus Zenfone 4 Pro ZS551KLiPhone 18 Pro
1. Display & Screen
Screen typeNot listedLTPO Super Retina XDR OLED, 120Hz, HDR10, Dolby Vision
Screen Size5.5"6.3"
Resolution & DensityN/A 1206 x 2622 pixels (19.5:9 ratio) (460 ppi)
Refresh Rate120 Hz120 Hz ProMotion
BrightnessN/A1000 nits (typ), 1600 nits (HBM), 3000 nits (peak)
Screen ProtectionNot listedCeramic Shield 2, Anti-reflective coating, Always-On display
2. Platform & Performance🏆 iPhone 18 Pro Wins Performance
Chipset / ProcessorSnapdragon 835 Apple A20 Pro (2 nm) (2nm)
CPU CoresNot listedHexa-core (2x High Performance + 4x Efficiency)
GPU GraphicsNot listedApple GPU (7-core graphics)
Operating SystemAndroid 15 iOS 27
3. Memory & Storage
RAM Memory6 GB LPDDR12GB LPDDR5X
Internal Storage128 GB256GB / 512GB / 1TB / 2TB
Storage SpeedNot listedNVMe fast flash
Card SlotNoNo
4. Main Camera Optics🏆 Asus Zenfone 4 Pro ZS551KL Wins Camera
Primary Camera50 MP, 50MP Main (OIS) + 50MP Ultra-wide + Telephoto48 MP, f/1.5, 24mm (wide), 1/1.28", 1.22µm, OIS, Dual pixel PDAF, Sensor-shift OIS (gen 2)
Telephoto ZoomNone (digital zoom only)48 MP (4x optical zoom), f/2.8, 100mm (periscope telephoto), OIS
Ultrawide CameraN/A48 MP, f/2.2, 13mm, 120˚ (ultrawide)
LiDAR / DepthNoneTOF 3D LiDAR scanner (depth sensing & night portrait)
5. Video
Main Camera Video
Not listed
4K@24/25/30/60/100/120fps1080p@240fps10-bit HDRDolby Vision HDR (up to 120fps)ProRes RAWApple Log 2Spatial 3D video & stereo sound
Front Video
Not listed
4K@24/25/30/60fps1080p@120fpsgyro-EISDolby Vision HDR
6. Selfie Camera
Selfie Lens32 MP18 MP, f/1.9, 20mm (ultrawide multi-aspect)
7. Body & Dimensions
DimensionsN/A150 x 71.9 x 8.8 mm (5.91 x 2.83 x 0.35 in)
WeightN/A211 g (7.44 oz)
Build MaterialsNot listedGlass front (Ceramic Shield 2), aluminum frame, aluminum/glass back
SIM TypeNot listedNano-SIM + eSIM + dual eSIM support
Water ResistanceNot listedIP68 dust/water resistant (up to 6m for 30 min)
8. Battery & Charging🏆 iPhone 18 Pro Wins Battery
Battery Capacity3,600 mAh4,288 mAh
Wired Fast ChargingN/A45W wired fast charging
Wireless ChargingNot listed25W wireless charging
Reverse ChargingNot listedNot listed
9. Sound & Audio
LoudspeakerNot listedYes, with stereo speakers (Spatial Audio)
3.5mm Headphone JackNoNo
10. Connectivity
Wi-Fi StandardNot listedWi-Fi 7 (802.11be, tri-band, hotspot)
BluetoothNot listedBluetooth 6.0, A2DP, LE
USB Port & SpeedNot listedUSB Type-C 3.2 Gen 2 (up to 10Gbps), DisplayPort video out
NFCYesYes (Apple Pay Visa, MasterCard, AMEX certified)
11. Sensors & Security
SensorsNot listedFace ID, LiDAR scanner, accelerometer, gyro, proximity, compass, barometer
Satellite FeaturesNot listedEmergency SOS, Messages and Find My via satellite
12. Colors & Overview
ColorsNot listedBlack, Silver, Glacier, Burgundy
Launch PricePrice on request$1,299
Our verdict

Asus Zenfone 4 Pro ZS551KL and iPhone 18 Pro are evenly matched

It's a close call. Pick the Asus Zenfone 4 Pro ZS551KL for its sharper main camera (50 MP vs 48 MP) and sharper selfie camera (32 MP vs 18 MP), or the iPhone 18 Pro for its bigger battery (4,288 mAh vs 3,600 mAh) and bigger screen (6.3" vs 5.5").

Buy Asus Zenfone 4 Pro ZS551KL if you want

Reliable all-round performance.

Buy iPhone 18 Pro if you want

Larger battery: 4,288 mAh vs 3,600 mAh · Optical telephoto zoom (1 telephoto lens)

Common questions

Which is better: Asus Zenfone 4 Pro ZS551KL or iPhone 18 Pro?

It's a close call. Pick the Asus Zenfone 4 Pro ZS551KL for its sharper main camera (50 MP vs 48 MP) and sharper selfie camera (32 MP vs 18 MP), or the iPhone 18 Pro for its bigger battery (4,288 mAh vs 3,600 mAh) and bigger screen (6.3" vs 5.5"). BeastScore: Asus Zenfone 4 Pro ZS551KL 89.0/100, iPhone 18 Pro 88.5/100.

What are the main battery and display differences between Asus Zenfone 4 Pro ZS551KL and iPhone 18 Pro?

Asus Zenfone 4 Pro ZS551KL has a 5.5-inch display and 3600 mAh battery. iPhone 18 Pro has a 6.3-inch display and 4288 mAh battery.

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