SmolLM3
A compact 3B model that punches above its size: dual-mode reasoning, six languages, and up to 128k-token context, released fully open with weights, data mixture, and training details.
SmolLM3 3B

Summary
Introduction
SmolLM3 is a 3B parameter language model designed to push the boundaries of small models. It supports dual-mode reasoning, 6 languages, and long context. SmolLM3 is a fully open model that offers strong performance at the 3B–4B scale.

The model is a decoder-only transformer using GQA and NoPE (with a 3:1 ratio). It was pretrained on 11.2T tokens with a staged curriculum of web, code, math, and reasoning data. Post-training included midtraining on 140B reasoning tokens, followed by supervised fine-tuning and alignment via Anchored Preference Optimization (APO).
Key features
- Instruct model optimized for hybrid reasoning
- Fully open model: open weights + full training details including public data mixture and training configs
- Long context: Trained on 64k context and supports up to 128k tokens using YARN extrapolation
- Multilingual: 6 natively supported (English, French, Spanish, German, Italian, and Portuguese)
Evaluation
In this section, we report the evaluation results of SmolLM3 model. All evaluations are zero-shot unless stated otherwise, and we use lighteval to run them.
We highlight the best score in bold and underline the second-best score.
Instruction Model
No Extended Thinking
Evaluation results of non-reasoning models and reasoning models in no-thinking mode. We highlight the best score in bold and underline the second-best score.
| Category | Metric | SmolLM3-3B | Qwen2.5-3B | Llama3.1-3B | Qwen3-1.7B | Qwen3-4B |
|---|---|---|---|---|---|---|
| High school math competition | AIME 2025 | 9.3 | 2.9 | 0.3 | 8.0 | 17.1 |
| Math problem-solving | GSM-Plus | 72.8 | 74.1 | 59.2 | 68.3 | 82.1 |
| Competitive programming | LiveCodeBench v4 | 15.2 | 10.5 | 3.4 | 15.0 | 24.9 |
| Graduate-level reasoning | GPQA Diamond | 35.7 | 32.2 | 29.4 | 31.8 | 44.4 |
| Instruction following | IFEval | 76.7 | 65.6 | 71.6 | 74.0 | 68.9 |
| Alignment | MixEval Hard | 26.9 | 27.6 | 24.9 | 24.3 | 31.6 |
| Tool Calling | BFCL | 92.3 | - | 92.3 * | 89.5 | 95.0 |
| Multilingual Q&A | Global MMLU | 53.5 | 50.54 | 46.8 | 49.5 | 65.1 |
(*): this is a tool calling finetune
Extended Thinking
Evaluation results in reasoning mode for SmolLM3 and Qwen3 models:
| Category | Metric | SmolLM3-3B | Qwen3-1.7B | Qwen3-4B |
|---|---|---|---|---|
| High school math competition | AIME 2025 | 36.7 | 30.7 | 58.8 |
| Math problem-solving | GSM-Plus | 83.4 | 79.4 | 88.2 |
| Competitive programming | LiveCodeBench v4 | 30.0 | 34.4 | 52.9 |
| Graduate-level reasoning | GPQA Diamond | 41.7 | 39.9 | 55.3 |
| Instruction following | IFEval | 71.2 | 74.2 | 85.4 |
| Alignment | MixEval Hard | 30.8 | 33.9 | 38.0 |
| Tool Calling | BFCL | 88.8 | 88.8 | 95.5 |
| Multilingual Q&A | Global MMLU | 64.1 | 62.3 | 73.3 |
Base Pre-Trained Model
English benchmarks
Note: All evaluations are zero-shot unless stated otherwise. For Ruler 64k evaluation, we apply YaRN to the Qwen models with 32k context to extrapolate the context length.
| Category | Metric | SmolLM3-3B | Qwen2.5-3B | Llama3-3.2B | Qwen3-1.7B-Base | Qwen3-4B-Base |
|---|---|---|---|---|---|---|
| Reasoning & Commonsense | HellaSwag | 76.15 | 74.19 | 75.52 | 60.52 | 74.37 |
| ARC-CF (Average) | 65.61 | 59.81 | 58.58 | 55.88 | 62.11 | |
| Winogrande | 58.88 | 61.41 | 58.72 | 57.06 | 59.59 | |
| CommonsenseQA | 55.28 | 49.14 | 60.60 | 48.98 | 52.99 | |
| Knowledge & Understanding | MMLU-CF (Average) | 44.13 | 42.93 | 41.32 | 39.11 | 47.65 |
| MMLU Pro CF | 19.61 | 16.66 | 16.42 | 18.04 | 24.92 | |
| MMLU Pro MCF | 32.70 | 31.32 | 25.07 | 30.39 | 41.07 | |
| PIQA | 78.89 | 78.35 | 78.51 | 75.35 | 77.58 | |
| OpenBookQA | 40.60 | 40.20 | 42.00 | 36.40 | 42.40 | |
| BoolQ | 78.99 | 73.61 | 75.33 | 74.46 | 74.28 | |
| Math & Code | ||||||
| Coding & math | HumanEval+ | 30.48 | 34.14 | 25.00 | 43.29 | 54.87 |
| MBPP+ | 52.91 | 52.11 | 38.88 | 59.25 | 63.75 | |
| MATH (4-shot) | 46.10 | 40.10 | 7.44 | 41.64 | 51.20 | |
| GSM8k (5-shot) | 67.63 | 70.13 | 25.92 | 65.88 | 74.14 | |
| Long context | ||||||
| Ruler 32k | 76.35 | 75.93 | 77.58 | 70.63 | 83.98 | |
| Ruler 64k | 67.85 | 64.90 | 72.93 | 57.18 | 60.29 | |
| Ruler 128k | 61.03 | 62.23 | 71.30 | 43.03 | 47.23 |
Multilingual benchmarks
| Category | Metric | SmolLM3 3B Base | Qwen2.5-3B | Llama3.2 3B | Qwen3 1.7B Base | Qwen3 4B Base |
|---|---|---|---|---|---|---|
| Main supported languages | ||||||
| French | MLMM Hellaswag | 63.94 | 57.47 | 57.66 | 51.26 | 61.00 |
| Belebele | 51.00 | 51.55 | 49.22 | 49.44 | 55.00 | |
| Global MMLU (CF) | 38.37 | 34.22 | 33.71 | 34.94 | 41.80 | |
| Flores-200 (5-shot) | 62.85 | 61.38 | 62.89 | 58.68 | 65.76 | |
| Spanish | MLMM Hellaswag | 65.85 | 58.25 | 59.39 | 52.40 | 61.85 |
| Belebele | 47.00 | 48.88 | 47.00 | 47.56 | 50.33 | |
| Global MMLU (CF) | 38.51 | 35.84 | 35.60 | 34.79 | 41.22 | |
| Flores-200 (5-shot) | 48.25 | 50.00 | 44.45 | 46.93 | 50.16 | |
| German | MLMM Hellaswag | 59.56 | 49.99 | 53.19 | 46.10 | 56.43 |
| Belebele | 48.44 | 47.88 | 46.22 | 48.00 | 53.44 | |
| Global MMLU (CF) | 35.10 | 33.19 | 32.60 | 32.73 | 38.70 | |
| Flores-200 (5-shot) | 56.60 | 50.63 | 54.95 | 52.58 | 50.48 | |
| Italian | MLMM Hellaswag | 62.49 | 53.21 | 54.96 | 48.72 | 58.76 |
| Belebele | 46.44 | 44.77 | 43.88 | 44.00 | 48.78 | |
| Global MMLU (CF) | 36.99 | 33.91 | 32.79 | 35.37 | 39.26 | |
| Flores-200 (5-shot) | 52.65 | 54.87 | 48.83 | 48.37 | 49.11 | |
| Portuguese | MLMM Hellaswag | 63.22 | 57.38 | 56.84 | 50.73 | 59.89 |
| Belebele | 47.67 | 49.22 | 45.00 | 44.00 | 49.00 | |
| Global MMLU (CF) | 36.88 | 34.72 | 33.05 | 35.26 | 40.66 | |
| Flores-200 (5-shot) | 60.93 | 57.68 | 54.28 | 56.58 | 63.43 |
The model has also been trained on Arabic (standard), Chinese and Russian data, but has seen fewer tokens in these languages compared to the 6 above. We report the performance on these langages for information.
| Category | Metric | SmolLM3 3B Base | Qwen2.5-3B | Llama3.2 3B | Qwen3 1.7B Base | Qwen3 4B Base |
|---|---|---|---|---|---|---|
| Other supported languages | ||||||
| Arabic | Belebele | 40.22 | 44.22 | 45.33 | 42.33 | 51.78 |
| Global MMLU (CF) | 28.57 | 28.81 | 27.67 | 29.37 | 31.85 | |
| Flores-200 (5-shot) | 40.22 | 39.44 | 44.43 | 35.82 | 39.76 | |
| Chinese | Belebele | 43.78 | 44.56 | 49.56 | 48.78 | 53.22 |
| Global MMLU (CF) | 36.16 | 33.79 | 39.57 | 38.56 | 44.55 | |
| Flores-200 (5-shot) | 29.17 | 33.21 | 31.89 | 25.70 | 32.50 | |
| Russian | Belebele | 47.44 | 45.89 | 47.44 | 45.22 | 51.44 |
| Global MMLU (CF) | 36.51 | 32.47 | 34.52 | 34.83 | 38.80 | |
| Flores-200 (5-shot) | 47.13 | 48.74 | 50.74 | 54.70 | 60.53 |
Parameters
Inputs
prompt- (text): User-provided input can be a question, a request, or the context to be addressed. The system uses the prompt to analyze, infer, and generate a corresponding response.
Output
output- (text): The content generated after the token is the final answer that the model returns to the user.
Usage for developers
Please find below the details to track the information and access the code for processing the model on our platform.
Requirements
pip install -r requirements.txt
Code based on AIOZ structure
import os
from transformers import AutoModelForCausalLM, AutoTokenizer
...
def do_ai_task(
prompt: Union[str, Path],
model_storage_directory: Union[str, Path],
device: Literal["cpu", "cuda", "gpu"] = "cpu",
*args, **kwargs) -> Any:
"""Define AI task: load model, pre-process, post-process, etc ..."""
# Define AI task workflow. Below is an example
model_weights = os.path.join(model_storage_directory, "SmolLM3-3B")
# load the tokenizer and the model
tokenizer = AutoTokenizer.from_pretrained(model_weights)
model = AutoModelForCausalLM.from_pretrained(
model_weights,
).to(device)
# Get and decode the output
output_ids = generated_ids[0][len(model_inputs.input_ids[0]) :]
output = tokenizer.decode(output_ids, skip_special_tokens=True)
return output
Reference
This repository is based on and inspired by the SmolLM team's work, including their open weights, training code, and public data mixture. We sincerely appreciate their generosity in sharing the model and full training details.
License
SmolLM3-3B is released under the Apache License 2.0, which permits use, modification, and redistribution for both commercial and non-commercial purposes. AIOZ AI redistributes this model in accordance with those terms. A full copy of the license is included in the LICENSE file, and attribution is provided in the NOTICE file.
Citation
@misc{bakouch2025smollm3,
title={{SmolLM3: smol, multilingual, long-context reasoner}},
author={Bakouch, Elie and Ben Allal, Loubna and Lozhkov, Anton and Tazi, Nouamane and Tunstall, Lewis and Patiño, Carlos Miguel and Beeching, Edward and Roucher, Aymeric and Reedi, Aksel Joonas and Gallouédec, Quentin and Rasul, Kashif and Habib, Nathan and Fourrier, Clémentine and Kydlicek, Hynek and Penedo, Guilherme and Larcher, Hugo and Morlon, Mathieu and Srivastav, Vaibhav and Lochner, Joshua and Nguyen, Xuan-Son and Raffel, Colin and von Werra, Leandro and Wolf, Thomas},
year={2025},
howpublished={\url{https://huggingface.co/blog/smollm3}}
}