Model reference · open weights

Solar-Open

Available as managed deployment Licence fee LLMs upstage Text gen 1 variants 15k dl/mo

Solar-Open is an open-weight language model from upstage. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.

Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.

What it is

Makerupstage
TypeLanguage models
TaskText gen
Parameters (lead)102.7B
Context128k tokens
Runs withtransformers
Released2025-12-10
Popularity15k downloads / month
LicenceCommercial licence needed

About

What Solar-Open is

Solar Open is Upstage's flagship 102B-parameter large language model, trained entirely from scratch and released under the Upstage Solar License (see LICENSE for details). As a Mixture-of-Experts (MoE) architecture, it delivers enterprise-grade performance in reasoning, instruction-following, and agentic capabilities—all while prioritizing transparency and customization for the open-source community.

Technical Report | Project Page

Highlights

  • MoE Architecture (102B / 12B): Built on a Mixture-of-Experts architecture with 102B total / 12B active parameters. This design delivers the knowledge depth of a massive model with the inference speed and cost-efficiency of a much smaller model.
  • Massive Training Scale: Pre-trained on 19.7 trillion tokens, ensuring broad knowledge coverage and robust reasoning capabilities across various domains.
  • Quantized Version Available: An official INT4 quantized model is provided by NotaAI and available at nota-ai/Solar-Open-100B-NotaMoEQuant-Int4.

Model Overview

  • Model Name: Solar Open 100B
  • Hugging Face ID: Upstage/Solar-Open-100B
  • Architecture: Mixture-of-Experts (MoE)
    • Total Parameters: 102.6B
    • Active Parameters: 12B (per token)
    • Experts: 129 Experts (top 8 among 128 Routed + 1 Shared)
  • Pre-training Tokens: 19.7 Trillion
  • Context Length: 128k
  • Training Hardware: NVIDIA B200 GPUs
  • License: Upstage Solar License (See LICENSE)
  • Hardware Requirements:
    • Minimum: 4x NVIDIA A100 (80GB)

For more details, please refer to the Solar Open Technical Report.

License

This repository contains both model weights and code, which are licensed under different terms:

  1. MODEL WEIGHTS (*.safetensors) Licensed under Upstage Solar License See: https://huggingface.co/upstage/Solar-Open-100B/blob/main/LICENSE

  2. CODE (*.py, *.json, *.jinja files) Licensed under Apache License 2.0 See: https://www.apache.org/licenses/LICENSE-2.0

Performance

Korean Benchmarks

CategoryBenchmarksSolar Open (102B)gpt-oss-120b (117B, high)gpt-oss-120b (117B, medium)GLM-4.5-Air (110B)
GeneralKMMLU73.072.770.370.2
KMMLU-Pro64.062.660.560.7
CLIcK78.977.272.948.3
HAE-RAE v1.173.370.869.642.6
KoBALT44.352.645.040.3
FinanceKBankMMLU (in-house)65.562.561.564.7
LawKBL65.562.860.160.6
MedicalKorMedMCQA84.475.876.380.5
MathKo-AIME 2024 (in-house)80.390.076.780.0
Ko-AIME 2025 (in-house)80.090.070.083.3
HRM8K87.689.584.886.0
IFKo-IFEval87.593.286.779.5
PreferenceKo Arena Hard v2 (in-house)79.979.573.860.4

English Benchmarks

CategoryBenchmarksSolar Open (102B)gpt-oss-120b (117B, high)gpt-oss-120b (117B, medium)GLM-4.5-Air (110B)
GeneralMMLU88.288.687.983.3
MMLU-Pro80.480.478.681.4
GPQA-Diamond68.178.069.475.8
HLE (text only)10.518.47.2310.8
MathAIME 202491.794.377.788.7
AIME 202584.391.775.082.7
HMMT 2025 (Feb)73.380.063.366.7
HMMT 2025 (Nov)80.073.366.770.0
CodeLiveCodeBench (v1–v6 cumul)74.289.982.871.9
IFIFBench53.770.861.237.8
IFEval88.091.486.586.5
PreferenceArena Hard v274.879.672.762.5
Writing Bench7.516.616.557.40
AgentTau² Airline52.456.052.860.8
Tau² Telecom55.657.747.428.1
Tau² Retail59.376.568.471.9
LongAA-LCR35.048.345.037.3

Inference Quickstart

We recommend using the following generation parameters:

temperature=0.8
top_p=0.95
top_k=50

Transformers

Install the required dependencies:

pip install -U "transformers>=5.0" kernels torch accelerate

Run inference with the following code:

import torch
from transformers import AutoModelForCausalLM, AutoTokenizer

MODEL_ID = "upstage/Solar-Open-100B"

# Load model and tokenizer
tokenizer = AutoTokenizer.from_pretrained(MODEL_ID)

model = AutoModelForCausalLM.from_pretrained(
    pretrained_model_name_or_path=MODEL_ID,
    torch_dtype=torch.bfloat16,
    device_map="auto",
)

# Prepare input
messages = [{"role": "user", "content": "who are you?"}]
inputs = tokenizer.apply_chat_template(
    messages,
    tokenize=True,
    add_generation_prompt=True,
    return_dict=True,
    return_tensors="pt",
)
inputs = inputs.to(model.device)

# Generate response
generated_ids = model.generate(
    **inputs,
    max_new_tokens=4096,
    temperature=0.8,
    top_p=0.95,
    top_k=50,
    do_sample=True,
)
generated_text = tokenizer.decode(generated_ids[0][inputs.input_ids.shape[1] :])
print(generated_text)

vLLM

Option 1: Using Docker (Highly Recommended)

Docker is the recommended deployment method for running Solar-Open-100B.

# For 8 GPUs
docker run --gpus all \
    --ipc=host \
    -p 8000:8000 \
    upstage/vllm-solar-open:latest \
    upstage/Solar-Open-100B \
    --trust-remote-code \
    --enable-auto-tool-choice \
    --tool-call-parser solar_open \
    --reasoning-parser solar_open \
    --logits-processors vllm.model_executor.models.parallel_tool_call_logits_processor:ParallelToolCallLogitsProcessor \
    --logits-processors vllm.model_executor.models.solar_open_logits_processor:Sola

From the published model card. Full card on the HuggingFace links in the sidebar.

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys solar-open for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (solar-open below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/chat/completions \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"solar-open","messages":[{"role":"user","content":"Hello"}]}'

Create an account — your API key is available in the console. 5M tokens/month currently included with every new account at launch.

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