Description:
Atom-350M-NVFP4 is the quantized version of TinyModels/Atom-350M, a compact open-source chat assistant fine-tuned from SmolLM2-360M-Instruct. Quantization was performed with llm-compressor using one-shot post-training quantization (PTQ). For more information on the base model, please check here.
This model is ready for commercial/non-commercial use.
This model is a quantized derivative of TinyModels/Atom-350M. See the Atom-350M Model Card for details on the base model's development and intended use.
License/Terms of Use:
Apache 2.0
Deployment Geography:
Global
Use Case:
Developers looking for an extremely compact, pre-quantized model for on-device inference, edge deployment, chatbots, and other resource-constrained AI applications.
Release Date:
Hugging Face 06/03/2026 via https://huggingface.co/syaffers/Atom-350M-NVFP4
Model Architecture:
Architecture Type: Transformers
Network Architecture: Decoder-only causal language model
Number of Model Parameters: ~360M
Input Type(s): Text
Input Format(s): String
Input Parameters: 1D (One Dimensional)
Other Properties Related to Input: Supports multi-turn conversations formatted via the model's chat template. Maximum context length of 8192 tokens.
Output:
Output Type(s): Text
Output Format: String
Output Parameters: 1D (One Dimensional)
Software Integration:
Supported Runtime Engine(s):
- Hugging Face Transformers
- vLLM (tested on v0.21.0)
Preferred Operating System(s):
Model Version(s):
The model is quantized to NVFP4 using llmcompressor.
Calibration Dataset:
Link: HuggingFaceH4/ultrachat_200k
Split: train_sft
Samples used: 1024
Data Collection Method: Automated
Labeling Method: Automated
Properties: UltraChat 200k is a large-scale, high-quality dataset of multi-turn conversational exchanges. Samples were formatted using the model's chat template and tokenized with truncation at 8192 tokens.
Inference:
Acceleration Engine: Hugging Face Transformers, vLLM
Test Hardware: NVIDIA GPU (CUDA)
Post Training Quantization
This model was obtained by quantizing the weights and activations of Atom-350M to the NVFP4 data type using one-shot PTQ via llm-compressor. All Linear layers within transformer blocks are quantized; the lm_head is excluded and kept at full precision to preserve output distribution.
Usage
from transformers import AutoModelForCausalLM, AutoTokenizer model = AutoModelForCausalLM.from_pretrained( "syaffers/Atom-350M-NVFP4", torch_dtype="auto", device_map="auto",)tokenizer = AutoTokenizer.from_pretrained("syaffers/Atom-350M-NVFP4") messages = [{"role": "user", "content": "Explain how a bicycle stays upright in simple terms."}]prompt = tokenizer.apply_chat_template(messages, tokenize=False, add_generation_prompt=True)inputs = tokenizer(prompt, return_tensors="pt").to(model.device) outputs = model.generate(**inputs, max_new_tokens=150, temperature=0.7)response = tokenizer.decode(outputs[0][inputs.input_ids.shape[1]:], skip_special_tokens=True)print(response)
vLLM — Offline Inference
Tested on vLLM v0.21.0 or later.
from vllm import LLM, SamplingParams llm = LLM(model="syaffers/Atom-350M-NVFP4", quantization="modelopt") sampling_params = SamplingParams(temperature=0.7, max_tokens=150) messages = [{"role": "user", "content": "Explain how a bicycle stays upright in simple terms."}]outputs = llm.chat(messages, sampling_params=sampling_params)print(outputs[0].outputs[0].text)
vLLM — Online Inference (OpenAI-Compatible Server)
Start the server:
vllm serve syaffers/Atom-350M-NVFP4 --quantization modelopt --port 8000
Then query it with the OpenAI client or any HTTP client:
from openai import OpenAI client = OpenAI(base_url="http://localhost:8000/v1", api_key="placeholder") response = client.chat.completions.create( model="syaffers/Atom-350M-NVFP4", messages=[{"role": "user", "content": "Explain how a bicycle stays upright in simple terms."}], max_tokens=150, temperature=0.7,)print(response.choices[0].message.content)
Model Limitations:
The base model was fine-tuned on data that may contain biases present in the source corpora. The NVFP4 quantization introduces a small degree of approximation error that may slightly affect output quality on edge cases. This model is not intended for safety-critical applications without additional guardrails.