Qwen3.5 4B — Hardware Requirements & GPU Compatibility
Vision
Qwen3.5 4B is a 4.7B-parameter open language model from Alibaba in the Qwen 3.5 family. It supports a context window of up to 262,144 tokens. At Q4_K_M it needs about 3.26 GB of VRAM — see which GPUs and Macs can run it below.
9.0M downloads
632 likesSpecifications
- Publisher
- Alibaba
- Family
- Qwen 3.5
- Parameters
- 4.7B
- Architecture
- Qwen3_5ForConditionalGeneration
- Context Length
- 262,144 tokens
- Vocabulary Size
- 248,320
- Release Date
- 2026-02-27
- License
- Apache 2.0
Get Started
HuggingFace
How Much VRAM Does Qwen3.5 4B Need?
Select a quantization to see compatible GPUs below.
| Quantization | Bits | VRAM | + Context | File Size | Quality |
|---|---|---|---|---|---|
| Q2_Kest. | 3.40 | 2.5 GB | 23.8 GB | 1.98 GB | 2-bit quantization with K-quant improvements |
| Q3_K_Mest. | 3.90 | 2.7 GB | 24.1 GB | 2.27 GB | 3-bit medium quantization |
| Q4_K_Mest. | 4.80 | 3.3 GB | 24.6 GB | 2.80 GB | 4-bit medium quantization — most popular sweet spot |
| Q5_K_Mest. | 5.70 | 3.8 GB | 25.1 GB | 3.32 GB | 5-bit medium quantization — good quality/size tradeoff |
| Q6_Kest. | 6.60 | 4.3 GB | 25.6 GB | 3.84 GB | 6-bit quantization, very good quality |
| Q8_0est. | 8.00 | 5.1 GB | 26.4 GB | 4.66 GB | 8-bit quantization, near-lossless |
| BF16est. | 16.00 | 9.8 GB | 31.1 GB | 9.32 GB | Brain floating point 16 — preferred for training |
est.= calculated VRAM estimate; no published GGUF file found for that quantization yet. Other rows are verified against real community uploads.
Which GPUs Can Run Qwen3.5 4B?
Q4_K_M · 3.3 GBQwen3.5 4B (Q4_K_M) requires 3.3 GB of VRAM to load the model weights. For comfortable inference with headroom for KV cache and system overhead, 5+ GB is recommended. Using the full 262K context window can add up to 21.3 GB, bringing total usage to 24.6 GB. 35 GPUs can run it, including NVIDIA GeForce RTX 5090, NVIDIA GeForce RTX 3090 Ti.
Runs great
— Plenty of headroomWhich Devices Can Run Qwen3.5 4B?
Q4_K_M · 3.3 GB33 devices with unified memory can run Qwen3.5 4B, including NVIDIA DGX H100, NVIDIA DGX A100 640GB.
Runs great
— Plenty of headroomRelated Models
Frequently Asked Questions
- How much VRAM does Qwen3.5 4B need?
Qwen3.5 4B requires 3.3 GB of VRAM at Q4_K_M, or 9.8 GB at BF16. Full 262K context adds up to 21.3 GB (24.6 GB total).
VRAM = Weights + KV Cache + Overhead
Weights = 4.7B × 4.8 bits ÷ 8 = 2.8 GB
KV Cache + Overhead ≈ 0.5 GB (at 2K context + ~0.3 GB framework)
KV Cache + Overhead ≈ 21.8 GB (at full 262K context)
VRAM usage by quantization
Q4_K_M3.3 GBQ4_K_M + full context24.6 GB- What's the best quantization for Qwen3.5 4B?
For Qwen3.5 4B, Q4_K_M (3.3 GB) offers the best balance of quality and VRAM usage. Q5_K_M (3.8 GB) provides better quality if you have the VRAM. The smallest option is Q2_K at 2.5 GB.
VRAM requirement by quantization
Q2_K2.5 GBQ4_K_M ★3.3 GBQ5_K_M3.8 GBQ6_K4.3 GBQ8_05.1 GBBF169.8 GB★ Recommended — best balance of quality and VRAM usage.
- Can I run Qwen3.5 4B on a Mac?
Qwen3.5 4B requires at least 2.5 GB at Q2_K, which exceeds the unified memory of most consumer Macs. You would need a Mac Studio or Mac Pro with a high-memory configuration.
- Can I run Qwen3.5 4B locally?
Yes — Qwen3.5 4B can run locally on consumer hardware. At Q4_K_M quantization it needs 3.3 GB of VRAM. Popular tools include Ollama, LM Studio, and llama.cpp.
- How fast is Qwen3.5 4B?
At Q4_K_M, Qwen3.5 4B can reach ~894 tok/s on AMD Instinct MI300X. On NVIDIA GeForce RTX 4090: ~201 tok/s. Speed depends mainly on GPU memory bandwidth. Real-world results typically within ±20%.
tok/s = (bandwidth GB/s ÷ model GB) × efficiency
Example: AMD Instinct MI300X → 5300 ÷ 3.3 × 0.55 = ~894 tok/s
Estimated speed at Q4_K_M (3.3 GB)
~894 tok/s~201 tok/s~668 tok/s~553 tok/sReal-world results typically within ±20%. Speed depends on batch size, quantization kernel, and software stack.
- What's the download size of Qwen3.5 4B?
At Q4_K_M, the download is about 2.80 GB. The full-precision BF16 version is 9.32 GB. The smallest option (Q2_K) is 1.98 GB.
- Which GPUs can run Qwen3.5 4B?
35 consumer GPUs can run Qwen3.5 4B at Q4_K_M (3.3 GB). Top options include AMD Radeon RX 6700 XT, AMD Radeon RX 6800, AMD Radeon RX 6800 XT. 35 GPUs have plenty of headroom for comfortable inference.
- Which devices can run Qwen3.5 4B?
33 devices with unified memory can run Qwen3.5 4B at Q4_K_M (3.3 GB), including Mac Mini M4 (16 GB), Mac Mini M4 (32 GB), Mac Mini M4 Pro (24 GB), Mac Mini M4 Pro (48 GB). Apple Silicon Macs use unified memory shared between CPU and GPU, making them well-suited for local LLM inference.