How to use from the
Use from the
Transformers library
# Use a pipeline as a high-level helper
from transformers import pipeline

pipe = pipeline("image-text-to-text", model="techwithsergiu/Qwen3.5-2B-bnb-4bit")
messages = [
    {
        "role": "user",
        "content": [
            {"type": "image", "url": "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/p-blog/candy.JPG"},
            {"type": "text", "text": "What animal is on the candy?"}
        ]
    },
]
pipe(text=messages)
# Load model directly
from transformers import AutoProcessor, AutoModelForImageTextToText

processor = AutoProcessor.from_pretrained("techwithsergiu/Qwen3.5-2B-bnb-4bit")
model = AutoModelForImageTextToText.from_pretrained("techwithsergiu/Qwen3.5-2B-bnb-4bit")
messages = [
    {
        "role": "user",
        "content": [
            {"type": "image", "url": "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/p-blog/candy.JPG"},
            {"type": "text", "text": "What animal is on the candy?"}
        ]
    },
]
inputs = processor.apply_chat_template(
	messages,
	add_generation_prompt=True,
	tokenize=True,
	return_dict=True,
	return_tensors="pt",
).to(model.device)

outputs = model.generate(**inputs, max_new_tokens=40)
print(processor.decode(outputs[0][inputs["input_ids"].shape[-1]:]))
Quick Links

Qwen3.5-2B-bnb-4bit

BNB NF4 4-bit quantization of Qwen/Qwen3.5-2B.

Retains the full visual tower — this is a VLM-capable model (image + text input). Primary use-case: Unsloth LoRA fine-tuning when you need image understanding in the fine-tuned result.

If you only need text fine-tuning, use techwithsergiu/Qwen3.5-text-2B-bnb-4bit instead — same backbone, visual tower removed, lighter VRAM footprint.

What was changed

  • Quantized with bitsandbytes NF4 double-quant (bnb_4bit_quant_type=nf4, bnb_4bit_compute_dtype=bfloat16)
  • Visual tower layers kept at bf16 (llm_int8_skip_modules) — required for correct image inference
  • lm_head.weight kept at bf16 for output quality

Model family

Model Type Base model
Qwen/Qwen3.5-2B f16 · VLM · source
techwithsergiu/Qwen3.5-2B-bnb-4bit BNB NF4 · VLM Qwen/Qwen3.5-2B
techwithsergiu/Qwen3.5-text-2B bf16 · text-only Qwen/Qwen3.5-2B
techwithsergiu/Qwen3.5-text-2B-bnb-4bit BNB NF4 · text-only Qwen3.5-text-2B
techwithsergiu/Qwen3.5-text-2B-GGUF GGUF quants Qwen3.5-text-2B

The visual tower is a bf16 overhead that scales with model size (~0.19 GB for 0.8B, ~0.62 GB for 2B/4B, ~0.85 GB for 9B). BNB-quantized models are roughly 40% of the original f16 size (exact ratio varies by size).

Fine-tuning

Text-only LoRA fine-tuning — use the text-only BNB variant as training base: techwithsergiu/Qwen3.5-text-2B-bnb-4bit

Training pipeline (QLoRA · Unsloth · TRL): github.com/techwithsergiu/qwen-qlora-train

VLM (image + text) fine-tuning — refer to the official Unsloth guide: unsloth.ai/docs/models/qwen3.5/fine-tune

Pipeline diagram

Conversion

Converted using qwen35-toolkit — a Python toolkit for BNB quantization, visual tower removal, verification and HF Hub publishing of Qwen3.5 models.


Acknowledgements

Based on Qwen/Qwen3.5-2B by the Qwen Team. If you use this model in research, please cite the original:

@misc{qwen3.5,
    title  = {{Qwen3.5}: Towards Native Multimodal Agents},
    author = {{Qwen Team}},
    month  = {February},
    year   = {2026},
    url    = {https://qwen.ai/blog?id=qwen3.5}
}
Downloads last month
242
Safetensors
Model size
2B params
Tensor type
F32
·
BF16
·
U8
·
Inference Providers NEW
This model isn't deployed by any Inference Provider. 🙋 Ask for provider support

Model tree for techwithsergiu/Qwen3.5-2B-bnb-4bit

Finetuned
Qwen/Qwen3.5-2B
Quantized
(100)
this model

Collection including techwithsergiu/Qwen3.5-2B-bnb-4bit