Highlights
ELYZA-Thinking-1.0-llm-jp-4-33b is a reasoning model by ELYZA, Inc., mid-trained and post-trained on llm-jp/llm-jp-4-33b-base for Japanese and English language understanding and generation.
- Fully domestic foundation. Built on llm-jp-4, pre-trained from scratch in Japan by LLM-jp; all further training was done by ELYZA.
- Focus on Japanese reasoning and instruction following. We localized high-quality math, coding and STEM reasoning data into Japanese and built Japanese instruction-following data with multiple checkable constraints, to improve Japanese reasoning and instruction following.
- Specialized in Japanese knowledge recall. We put particular care into Japanese-specific knowledge by synthesizing knowledge data from Japanese Wikipedia and Wikidata and training on it, to improve the model's understanding and recall of Japanese knowledge.
Benchmarks are first averaged within 7 capability groups, then across the groups (Japanese / English: that language's benchmarks only).
MoE models

Dense models

Benchmark Results
Per-benchmark scores of the dense models above. For the MoE models, see the model card of elyza/ELYZA-Thinking-1.0-llm-jp-4-32b-a3b.
Model Overview
Three training stages on top of llm-jp/llm-jp-4-33b-base, all done by ELYZA:
Mid-training: a broader foundation for knowledge, reasoning and agentic use.
- Math, coding and STEM problems were translated into Japanese and given newly generated reasoning; the original English data was kept as well.
- Agentic data was localized into Japanese while keeping tool calls, function names, arguments and JSON intact.
SFT: the answer format and Japanese ability.
- Several million synthesized SFT examples with thinking traces, about half of them high-quality Japanese data; answers were generated by a teacher model and kept only when a program verified them (math equivalence, unit tests, rule checkers).
- Complex instructions with multiple checkable constraints, including Japanese-specific ones such as furigana and kanji numerals.
- Japanese knowledge data synthesized from the latest Japanese Wikipedia and Wikidata.
Reinforcement learning (RLVR): accuracy on hard problems that imitation alone does not reach.
- Verifiable problems across math, coding, Japanese knowledge, complex instruction following and tool use, trained together in one run.
- Rewards are computed by programs: answer equivalence, test execution, constraint checkers, and call matching or the final environment state for tool use.
- Problems were selected so the model sometimes, but not reliably, solves them; reward loopholes (answers that score without solving) were found and closed before training.
See also the sibling model elyza/ELYZA-Thinking-1.0-llm-jp-4-32b-a3b.
Quickstart
vLLM (recommended)
- Install vLLM (tested with 0.30.0) and FlashInfer's prebuilt kernels, so no local CUDA toolkit is needed:
pip install vllm==0.30.0pip install flashinfer-jit-cache==0.6.18.post1 --extra-index-url https://flashinfer.ai/whl/cu130
- Download the plugins:
hf download elyza/ELYZA-Thinking-1.0-llm-jp-4-33b --include "vllm_plugins/*" --local-dir .
- Start the server:
vllm serve elyza/ELYZA-Thinking-1.0-llm-jp-4-33b \ --max-model-len 65536 \ --trust-remote-code \ --reasoning-parser-plugin vllm_plugins/multi_parser_loader.py \ --reasoning-parser llmjp4 \ --tool-parser-plugin vllm_plugins/llmjp_harmony_tool_parser.py \ --tool-call-parser llmjp_harmony \ --enable-auto-tool-choice
- Send a request. The answer is returned in
content, and the reasoning separately in the message's reasoning field:
curl http://localhost:8000/v1/chat/completions \ -H "Content-Type: application/json" \ -d '{ "model": "elyza/ELYZA-Thinking-1.0-llm-jp-4-33b", "messages": [{"role": "user", "content": "仕事の熱意を取り戻すためのアイデアを5つ挙げてください。"}], "temperature": 0.6, "top_p": 0.95 }'
Tool calling uses the standard OpenAI tools field; calls come back in tool_calls. The bundled tool parser sets the decoding options it needs (keeping the <|call|> marker), so no extra request parameters are required:
curl http://localhost:8000/v1/chat/completions \ -H "Content-Type: application/json" \ -d '{ "model": "elyza/ELYZA-Thinking-1.0-llm-jp-4-33b", "messages": [{"role": "user", "content": "東京の天気を教えて"}], "tools": [{ "type": "function", "function": { "name": "get_weather", "description": "Get the current weather of a city", "parameters": {"type": "object", "properties": {"city": {"type": "string"}}, "required": ["city"]} } }] }'
Works with the latest Transformers (tested with 4.57.6 and 5.18.0):
pip install -U transformers accelerate torch
import torchfrom transformers import AutoTokenizer, AutoModelForCausalLM model_name = "elyza/ELYZA-Thinking-1.0-llm-jp-4-33b" tokenizer = AutoTokenizer.from_pretrained(model_name, trust_remote_code=True)model = AutoModelForCausalLM.from_pretrained( model_name, device_map="auto", dtype=torch.bfloat16, trust_remote_code=True,)model.eval() messages = [{"role": "user", "content": "仕事の熱意を取り戻すためのアイデアを5つ挙げてください。"}]inputs = tokenizer.apply_chat_template( messages, add_generation_prompt=True, return_tensors="pt", return_dict=True).to(model.device) with torch.no_grad(): output_ids = model.generate( **inputs, max_new_tokens=16384, # thinking model: leave room for the reasoning before the answer do_sample=True, temperature=0.6, top_p=0.95, )[0][inputs["input_ids"].shape[-1]:] for m in tokenizer.parse_harmony_message(output_ids.tolist()): print(f"[{tokenizer.decode(m.channel.token_ids)}]", tokenizer.decode(m.content.token_ids))
💡 Tip
Recommended sampling: temperature=0.6, top_p=0.95 (default in generation_config.json).
Acknowledgements
We thank LLM-jp, led by the Research and Development Center for Large Language Models at the National Institute of Informatics, for developing the llm-jp-4 models from scratch in Japan and releasing them under a generous open license. This model is built on llm-jp/llm-jp-4-33b-base, and part of our SFT data comes from llm-jp/llm-jp-4-thinking-sft-data.
How to Cite
@misc{elyza2026thinking, title={elyza/ELYZA-Thinking-1.0-llm-jp-4-33b}, url={https://huggingface.co/elyza/ELYZA-Thinking-1.0-llm-jp-4-33b}, author={Xin Zhao, Congda Ma, Satoshi Tohda, Tasavat Trisitichoke, Akira Sasaki, Masato Hirakawa, Kota Kakiuchi}, year={2026},}
Citations
@misc{llm-jp-4-33b-base, title = {llm-jp/llm-jp-4-33b-base}, url = {https://huggingface.co/llm-jp/llm-jp-4-33b-base}, author = {Research and Development Center for Large Language Models}, year = {2026}}