Xiaomi 15 vs Xiaomi 15 Ultra

Xiaomi 15

The 6.36-inch 1.5K LTPO OLED is sharp, vibrant, and incredibly bright at 3,200 nits peak (tested up to 3,593 nits HDR). Ultra-narrow 1.38mm bezels and high-frequency PWM dimming above 3,000Hz round out an excellent display package, though OLED smear at lower brightness is a noted concern.

• Peak brightness tested at 3,593 nits in HDR — among the brightest compact phone displays available
• Ultra-narrow 1.38mm bezels with excellent color accuracy in Original Color PRO profile
• OLED smear visible at lower brightness levels (0-70% range) — a recurring user complaint

Xiaomi 15 Ultra

A stunning 6.73-inch 2K LTPO AMOLED with 120Hz, 3,200 nits peak brightness, and Dolby Vision support.

• 3,200 nits peak brightness is the highest of any smartphone tested, with excellent outdoor visibility and HDR performance
• 2K resolution with 120Hz LTPO delivers incredibly sharp, smooth visuals for gaming and media consumption

Xiaomi 15

The Snapdragon 8 Elite with 12GB RAM delivers flagship-tier performance that's smooth and snappy for everyday use, gaming, and multitasking. However, the compact body struggles to dissipate heat under sustained loads, causing notable thermal throttling during extended gaming sessions.

• Snapdragon 8 Elite scores ~2,990 single-core and ~9,114 multi-core on Geekbench 6 — genuinely fast
• Thermal throttling is a real issue — fails to complete 3DMark GPU stress tests and gets uncomfortably hot
• CPU throttles to 72-77% of peak under sustained load — compact chassis limits cooling capacity

Xiaomi 15 Ultra

Snapdragon 8 Elite with 16GB RAM delivers the fastest Android performance available with excellent thermal management.

• Snapdragon 8 Elite with 16GB RAM makes this one of the fastest phones tested — no app or game can slow it down
• Liquid cooling system keeps sustained performance high with minimal throttling during extended gaming sessions
• 16GB RAM ensures smooth multitasking with dozens of apps in memory and efficient AI processing

Xiaomi 15

The triple 50MP Leica system shines with its main sensor and improved 2.6x telephoto, earning a DxOMark score of 146. Leica color profiles produce natural, pleasing images with excellent dynamic range. The ultrawide camera is the clear weakness, with noticeably more noise in low light and no autofocus.

• 50MP main Leica Summilux camera delivers excellent photo quality with natural colors and strong dynamic range
• 2.6x optical telephoto is a meaningful upgrade over the Xiaomi 14 — sharp and versatile
• Ultrawide camera is the weakest link — subpar quality, no autofocus, noticeably more noise in low light
• DxOMark camera score of 146 — good but not class-leading among 2025 flagships

Xiaomi 15 Ultra

The crown jewel — a triple Leica camera system with a 1-inch main sensor, 200MP telephoto, and 50MP ultrawide that redefines smartphone photography.

• The 1-inch main sensor captures more light and detail than any competing smartphone camera — photos have a depth and quality that approaches dedicated cameras
• 200MP telephoto with 4.3x optical zoom produces incredibly detailed zoom shots that rival the Galaxy S25 Ultra's 5x periscope
• Leica color science produces warm, film-like tones with natural skin rendering that photographers love
• Video stabilization is the best on any Android phone, though color consistency and dynamic range in video still trail the iPhone