OpenThai 2.0

Chat completions on OpenThai 2.0, an open-weight Thai vision-language model, through an OpenAI-compatible endpoint.

POST/v3/llm/openthai2p0/chat/completionsTry it

• Price0.01 / 0.02 ICper 1k tokens, in / out
• Served27Kcalls

• v1.0
• Active

Input

model

openthai2.0

messages

role: user content: อากรแสตมป์กับภาษีมูลค่าเพิ่มต่างกันอย่างไร

OutputPOST /v3/llm/openthai2p0/chat/completions

id

chatcmpl-...

model

openthai2.0-qwen3.8-27b

choices

message: { role, content, reasoning }

usage

prompt_tokens: 68 completion_tokens: 84

Every field, under Response

Request

curl -X POST 'https://api.iapp.co.th/v3/llm/openthai2p0/chat/completions' \
  -H 'apikey: YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{ \
    "model": "openthai2.0", \
    "messages": [ \
      {"role": "user", "content": "อากรแสตมป์กับภาษีมูลค่าเพิ่มต่างกันอย่างไร"} \
    ] \
  }'

Response

200OK. The fields are explained under Response.

{
  "id": "chatcmpl-...",
  "model": "openthai2.0-qwen3.8-27b",
  "choices": [
    {"message": {
      "role": "assistant",
      "content": "อากรแสตมป์และภาษีมูลค่าเพิ่มต่างกันทั้งฐานภาษีและวิธีจัดเก็บ ...",
      "reasoning": "The user asks about the difference between stamp duty and VAT ..."
    }}
  ],
  "usage": {"prompt_tokens": 68, "completion_tokens": 84}
}

Request

JSON, in the OpenAI chat-completions shape; the OpenAI SDK works as-is with the base URL https://api.iapp.co.th/v3/llm/openthai2p0 and the key as apikey or Authorization: Bearer. The context window is 262,144 tokens.

Headers

apikeystringrequired

Your API key, created under API Keys in the control panel.

Body

modelstringrequired

openthai2.0, the one model this route serves.

messagesarrayrequired

The conversation. A message's content is a string, or a list of parts mixing text and image_url, the image a public URL or a Base64 data URI up to 50 MB.

max_tokensinteger

Leave unset, or 8,192 or more: the model reasons before it answers and a small cap can starve the reply.

temperaturefloat

Default 1.0 for questions; 0.0 for transcription and for output a machine will parse.

chat_template_kwargsobject

{"enable_thinking": false} turns the reasoning off, for clean transcription.

toolsarray

OpenAI function-calling, for agents.

streamboolean

true for server-sent events.

Price

A call costs 0.01 IC per 1K input tokens and 0.02 IC per 1K output tokens.

Response

The OpenAI chat-completion object, as in the panel. The model reasons first; the server puts the reasoning in message.reasoning and only the answer in message.content, so OpenAI SDK code needs no change. For a short or JSON-only answer, say so in the prompt: "ตอบสั้น ๆ", "ตอบเป็น JSON เท่านั้น".

The OpenAI chat-completion object, as in the panel. The model reasons first; the server puts the reasoning in message.reasoning and only the answer in message.content, so OpenAI SDK code needs no change. For a short or JSON-only answer, say so in the prompt: "ตอบสั้น ๆ", "ตอบเป็น JSON เท่านั้น".

Details

Measured

Measure	Result
Thai handwriting, character error rate	0.261, against 0.649 for its base model
Books and Royal Gazette pages, character error rate	0.126
Printed documents, character error rate	0.077
OpenThaiEval, Thai national exams	0.842
Instruction following, IFEval-TH	0.795
Tool use, BFCL overall	0.820

Full results are on the model page; the weights are on Hugging Face and Ollama, and the model answers in the browser at chinda3.iapp.co.th.

Limits

• 30 requests per minute per key.
• The model can still hallucinate on illegible input and is not evaluated for medical or legal advice; for Thai law, use OpenThai 2.0 Legal, which retrieves the statute first.

Data handling

Prompts, images and completions are processed in memory and not kept after the response. The service is GDPR and PDPA compliant, and the same model runs on your own hardware.