llamaperf

M4 Max 128GB vs M5 Max 36GB for local LLMs

52 reports on the M4 Max 128GB and 12 on the M5 Max 36GB

Which is faster for local LLMs?

On Qwen3.5 9B at 4-bit, the M4 Max 128GB has 68.0 generation tokens/s (one run); prompt processing 832.1 tokens/s (one run); the M5 Max 36GB has 80.1 generation tokens/s (one run). Those are community reports whose engines and settings differ, so the gap is a rough sign, not a controlled measure of the two cards. Memory bandwidth, which caps how fast a card can write, is 19% higher on the M4 Max 128GB (546 GB/s on the M4 Max 128GB, 461 on the M5 Max 36GB). Across 2 shared models with generation measurements on both cards, the M4 Max 128GB's median is higher on 0 and the M5 Max 36GB's on 2.

M4 Max 128GB
Memory
128GB unified
Memory bandwidth
546 GB/s
FP16 compute
18.4 TFLOPS
Reports
52
M5 Max 36GB
Memory
36GB unified
Memory bandwidth
461 GB/s
FP16 compute
not on record
Reports
12

Measured on both

Generation and prompt processing speeds from plain runs (one device, one request, no speculative decoding, the whole model in the device's memory) of the same model size at the same bit class. Each side shows the engines and reported context behind its median. Context can mean a configured window or prompt depth, so these are community comparisons with differing settings. How to read these

ModelM4 Max 128GBM5 Max 36GB
Qwen3.5 9B4-bit68.0one runPP 832.1 (one run)llama.cppcontext not stated80.1one runengine not statedcontext not stated
Qwen3.8 27B4-bit21.8one runPP 236.6 (one run)llama.cppcontext not stated25.8one runengine not statedcontext not stated

Estimated by the calculator

The quant the calculator recommends for each card and its estimated speed at a 32,768-token context with 32 GB of system RAM, from memory bandwidth and the model's shape. Where a model was also measured above, the measurement wins.

ModelM4 Max 128GBM5 Max 36GB
Qwen3.5 9B20.2 t/sFP1620.3 t/sFP16
Qwen3.8 27B6.7 t/sFP1619.7 t/sQ5_K_M
Qwen3.8 125B · 6B active30.7 t/sQ5_K_Sdoesn't fit at these settings
Qwen3.6 35B · 3B active21.2 t/sFP1675.9 t/sQ4_K_M
DeepSeek V4 Flash 284B · 13B active48.3 t/sQ2_Kdoesn't fit at these settings
Qwen3.6 27B6.7 t/sFP1619.7 t/sQ5_K_M
Gemma 4 26B · 4B active18.2 t/sFP1650.2 t/sQ5_K_M
DeepSeek V4.1 Flash 552B · 16B activedoesn't fit at these settingsdoesn't fit at these settings

Change the context, RAM or model in the calculator: M4 Max 128GB · M5 Max 36GB

Every report on each card, with its source: M4 Max 128GB · M5 Max 36GB

More comparisons