How much VRAM does Qwen3.5 4B need?

Qwen3.5 4B (4B parameters) requires approximately 7.0 GB of memory with Q4_K_M quantization.

What is the best quantization for Qwen3.5 4B?

The recommended quantization for Qwen3.5 4B is Q4_K_M, which balances quality and memory efficiency.

Can it run?

Yes, MacBook Air M4 24GB can run Qwen3.5 4B with a C grade (Runs well). Expected decode speed: 32.0 tok/s.

CUsable

Runs well

Using Q4_K_M in Ollama

Capabilities:

Fit status

Runs well

Decode

32.0 tok/s

TTFT

6056 ms

Safe context

39K

Memory

7.0 GB / 17.3 GB

Weights2.4 GB

KV Cache0.8 GB

Runtime1.2 GB

Headroom2.6 GB

Workload	Grade	Fit	Decode	TTFT	Context
Agentic Coding	C	Runs well	35.4 tok/s	7953 ms	74K
Chat	C	Runs well	35.4 tok/s	2982 ms	20K
Coding	C	Runs well	32.0 tok/s	6056 ms	39K
RAG	C	Runs well	35.4 tok/s	9941 ms	74K
Reasoning	C	Runs well	35.4 tok/s	6461 ms	39K

How Qwen3.5 4B (4B params) fits at each quantization level on MacBook Air M4 24GB (17.3 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	1.6 GB	Low	D31
Q3_K_S	3	2.0 GB	Low	D32
NVFP4	4

Upgrade options

RX 7900 XT 20GBBudget pick

C196.7 tok/s decode

~$899 MSRP

RX 7900 XTX 24GBBest value

C283.3 tok/s decode

~$999 MSRP