How much VRAM does Qwen3.5 4B need?

Qwen3.5 4B (4B parameters) requires approximately 6.2 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 M1 16GB can run Qwen3.5 4B with a C grade (Runs well). Expected decode speed: 18.1 tok/s.

CUsable

Runs well

Using Q4_K_M in Ollama

Capabilities:

Fit status

Runs well

Decode

18.1 tok/s

TTFT

10687 ms

Safe context

30K

Memory

6.2 GB / 11.5 GB

Weights2.4 GB

KV Cache0.8 GB

Runtime1.2 GB

Headroom1.7 GB

Workload	Grade	Fit	Decode	TTFT	Context
Agentic Coding	C	Runs well	16.7 tok/s	16841 ms	56K
Chat	C	Runs well	16.7 tok/s	6315 ms	15K
Coding	C	Runs well	18.1 tok/s	10687 ms	30K
RAG	C	Runs well	16.7 tok/s	21051 ms	56K
Reasoning	C	Runs well	16.7 tok/s	13683 ms	30K

How Qwen3.5 4B (4B params) fits at each quantization level on MacBook Air M1 16GB (11.5 GB usable).

Quant	Bits	VRAM	Quality	Fit
Q2_K	2	1.6 GB	Low	D32
Q3_K_S	3	2.0 GB	Low	D33
NVFP4	4

Upgrade options

Intel Arc B580 12GBBudget pick

C89.7 tok/s decode

~$249 MSRP

RTX 3060 12GBBest value

C97.4 tok/s decode

~$329 MSRP

MacBook Pro M4 Pro 24GBApple upgrade

C86.2 tok/s decode

~$1,999 MSRP

RTX A2000 12GB