llamaperf

M4 24GB vs M4 Max 128GB for local LLMs

8 reports on the M4 24GB and 52 on the M4 Max 128GB

Which is faster for local LLMs?

On Gemma 4 12B at 4-bit, the M4 24GB has 12.9 generation tokens/s (one run); prompt processing 138.5 tokens/s (one run); the M4 Max 128GB has 54.5 generation tokens/s (one run); prompt processing 589.0 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 4.6x higher on the M4 Max 128GB (120 GB/s on the M4 24GB, 546 on the M4 Max 128GB). Across 3 shared models with generation measurements on both cards, the M4 24GB's median is higher on 0 and the M4 Max 128GB's on 3.

M4 24GB
Memory
24GB unified
Memory bandwidth
120 GB/s
FP16 compute
4.3 TFLOPS
Reports
8
M4 Max 128GB
Memory
128GB unified
Memory bandwidth
546 GB/s
FP16 compute
18.4 TFLOPS
Reports
52

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 24GBM4 Max 128GB
Gemma 4 12B4-bit12.9one runPP 138.5 (one run)llama.cppcontext not stated54.5one runPP 589.0 (one run)llama.cppcontext not stated
Qwen3.5 9B4-bit17.4one runOllama4K context68.0one runPP 832.1 (one run)llama.cppcontext not stated
Qwen3.8 27B4-bit6.5one runPP 60.8 (one run)llama.cppcontext not stated21.8one runPP 236.6 (one run)llama.cppcontext 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 24GBM4 Max 128GB
Gemma 4 12B9.4 t/sQ6_K15.2 t/sFP16
Qwen3.5 9B10.1 t/sQ8_020.2 t/sFP16
Qwen3.8 27B10.8 t/sQ2_K6.7 t/sFP16
Qwen3.8 125B · 6B activedoesn't fit at these settings30.7 t/sQ5_K_S
Qwen3.6 35B · 3B active35.8 t/sQ2_K21.2 t/sFP16
DeepSeek V4 Flash 284B · 13B activedoesn't fit at these settings48.3 t/sQ2_K
Qwen3.6 27B10.8 t/sQ2_K6.7 t/sFP16
Gemma 4 26B · 4B active24.1 t/sQ3_K_S18.2 t/sFP16
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 24GB · M4 Max 128GB

Every report on each card, with its source: M4 24GB · M4 Max 128GB

More comparisons