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NLU Released Large Language Model Apache-2.0

Chinda LLM 4B: Thailand's sovereign open LLM

An open-weight Thai-first large language model with thinking-mode reasoning, built on Qwen3-4B and released under Apache-2.0.

Sizes
4B
Languages
Thai, English
Published
March 19, 2025
Authors
iApp Technology, AIEAT

What it is#

Chinda LLM 4B is iApp Technology’s open-weight Thai sovereign large language model, developed in collaboration with AIEAT (the AI Engineering Association of Thailand). Built on the Qwen3-4B architecture and optimized for Thai, it brings strong Thai language understanding and generation, plus step-by-step thinking-mode reasoning for math, logic, and code, into an efficient 4-billion-parameter model you can run yourself.

The weights are open under Apache-2.0, so anyone can download, run, and fine-tune the model freely — for research or in production.

Key capabilities#

  • Thai-first — trained and tuned specifically for Thai language understanding and generation.
  • Thinking mode — explicit step-by-step reasoning for math, code, and logic problems.
  • Long context — handles up to 40,960 tokens, enough for long Thai documents.
  • Efficient — a 4B model runs on a single consumer GPU (~8 GB), or locally via Ollama / LM Studio / OpenWebUI.
  • Open & OpenAI-compatible — open weights under Apache-2.0, and an OpenAI-compatible API for drop-in integration.

Benchmarks#

Evaluated head-to-head against another strong 4B Thai model, Typhoon 2.1 Gemma3 4B, Chinda LLM 4B leads on overall average and on most reasoning, code, and Thai-exam benchmarks.

BenchmarkLanguageChinda 4BTyphoon 2.1 4B
AIME24English0.5330.100
AIME24Thai0.1000.000
LiveCodeBenchEnglish0.6650.209
LiveCodeBenchThai0.1980.144
MATH500English0.9080.702
MATH500Thai0.6120.566
IFEvalEnglish0.8490.848
IFEvalThai0.6830.740
Language Accuracy (code-switching)Thai0.9840.992
OpenThaiEvalThai0.6510.544
Average0.5690.414

Source: OpenThaiGPT benchmark suite (2024–2025). Higher is better.

How to use#

Load the model with the Hugging Face Transformers library and apply the chat template:

from transformers import AutoModelForCausalLM, AutoTokenizer

model_name = "iapp/chinda-qwen3-4b"
tokenizer = AutoTokenizer.from_pretrained(model_name)
model = AutoModelForCausalLM.from_pretrained(model_name, device_map="auto")

messages = [
    {"role": "user", "content": "สวัสดีครับ ช่วยอธิบายเกี่ยวกับปัญญาประดิษฐ์ให้ฟังหน่อย"}
]
text = tokenizer.apply_chat_template(
    messages, tokenize=False, add_generation_prompt=True
)

inputs = tokenizer(text, return_tensors="pt").to(model.device)
outputs = model.generate(**inputs, max_new_tokens=512, temperature=0.7)
print(tokenizer.decode(outputs[0][inputs.input_ids.shape[-1]:], skip_special_tokens=True))

It also runs locally with Ollama, LM Studio, and OpenWebUI, and is available through an OpenAI-compatible API.

Use cases#

  • Conversational AI — natural Thai chatbots and virtual assistants.
  • Content generation — Thai articles, summaries, and marketing copy.
  • Document understanding — read and summarize long Thai documents.
  • Reasoning — math, logic, and code with step-by-step thinking.
  • Education — Thai-language tutoring and explanations.

Availability#

Chinda LLM 4B on Hugging Face. Open weights, Apache-2.0.

Use this model

Get the weights and start building.