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Solar Mini 4 API: toman pricing and code

upstage/solar-mini4

Tool callingReasoningJSON output
Create a keyTry it
Input · per 1M tokens
17,311 toman
Output · per 1M tokens
69,244 toman
One 1,000-word request ≈
113 toman

You are billed for the usage the request actually reported. Prices follow the market. Cached input: 1,731 toman per 1M tokens.Pricing and top-ups

Solar Mini 4 example: JSON output against a schema

The example is picked from this model's own capabilities. Drop in your key and it runs as is.

from openai import OpenAI
import json

client = OpenAI(base_url="https://api.uttapen.ir/v1", api_key="sk-up-…")

schema = {
    "name": "ticket",
    "schema": {
        "type": "object",
        "properties": {
            "category": {"type": "string", "enum": ["fani", "mali", "forush"]},
            "priority": {"type": "integer", "minimum": 1, "maximum": 5},
            "summary": {"type": "string"},
        },
        "required": ["category", "priority", "summary"],
        "additionalProperties": False,
    },
    "strict": True,
}

resp = client.chat.completions.create(
    model="upstage/solar-mini4",
    messages=[{"role": "user", "content": "Ticket: "For two days I cannot download my invoice and I was charged twice.""}],
    response_format={"type": "json_schema", "json_schema": schema},
)
print(json.loads(resp.choices[0].message.content))
import OpenAI from "openai";

const client = new OpenAI({ baseURL: "https://api.uttapen.ir/v1", apiKey: "sk-up-…" });

const resp = await client.chat.completions.create({
  model: "upstage/solar-mini4",
  messages: [{ role: "user", content: "Ticket: "For two days I cannot download my invoice and I was charged twice."" }],
  response_format: {
    type: "json_schema",
    json_schema: {
      name: "ticket",
      strict: true,
      schema: {
        type: "object",
        properties: {
          category: { type: "string", enum: ["fani", "mali", "forush"] },
          priority: { type: "integer", minimum: 1, maximum: 5 },
          summary: { type: "string" },
        },
        required: ["category", "priority", "summary"],
        additionalProperties: false,
      },
    },
  },
});
console.log(JSON.parse(resp.choices[0].message.content));
curl https://api.uttapen.ir/v1/chat/completions \
  -H "Authorization: Bearer sk-up-…" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "upstage/solar-mini4",
    "messages": [{"role": "user", "content": "Classify the ticket and give it a priority from 1 to 5."}],
    "response_format": {"type": "json_object"}
  }'

What is Solar Mini 4 good for?

Solar Mini 4 comes from Upstage; in uttapen you reach it with the model id "upstage/solar-mini4". It accepts up to 524,288 tokens of input per call, so a long document or several source files fit in a single request. A single response can run to 131,072 tokens. On price it sits in the "very cheap" band — cheaper than 355 and dearer than 35 of the other paid models in the catalogue.

What it can do beyond plain text: it supports tool calling, so it can invoke your own functions with valid arguments; it returns schema-valid JSON through response_format, ready to hand to your code; it has a reasoning mode that pays off on multi-step problems, maths and debugging. All of it works through the standard parameters of the official OpenAI SDK — no custom client, no wrapper. Keep in mind that reasoning tokens are output tokens and do appear on the bill.

Pricing is 17,311 toman per 1M input tokens and 69,244 per 1M output tokens. A 1,000-word round trip on Solar Mini 4 lands near 113 toman. It supports cached input: repeated context is billed at 1,731 toman per 1M, which matters a lot if your system prompt is long. You are always charged for the usage the request actually reported, never for the estimate, and a failed request costs nothing.

The closest alternative with the same capabilities from a different provider is Nemotron 3.5 Lightning: Solar Mini 4 works out about 9% cheaper, and its context window is larger. Both run on the same key and the same code, so trying the other one is a single string change.

To make the figure concrete: 100,000 toman of credit buys roughly 885 thousand-word requests on Solar Mini 4, and every 1,000 toman is about 8,850 words of round trip. A job with one million input tokens and one million output tokens comes to 86,555 toman in total. Filling this model's 524,288-token window costs 9,076 toman on the input side alone, which is the real reason to keep conversation history short.

Its nearest relative in the catalogue is "upstage/solar-pro4", and choosing between those two is where most people hesitate. On a thousand-word request this variant works out about 3× cheaper (113 against 338 toman).

Upstage has 2 models in our catalogue; the cheapest is Solar Mini 4 at 113 toman per thousand words and the dearest Solar Pro 4 at 338. Among the less common parameters it accepts parallel_tool_calls, presence_penalty, reasoning_effort — all through the standard request body. It does not support seed, which most models here do, so test before switching if your code relies on them. By context size the nearest option from another provider is Llama 4 Maverick at 524,288 tokens.

Good fits: high-volume work such as classification, tagging and bulk summarising, logic puzzles and code review, agents that reach out to APIs and databases, extracting data against a fixed schema, analysing a long document or codebase in one request.

Provider's own description

Solar Mini 4 is Upstage's compact, cost-efficient language model, a 35B-parameter mixture-of-experts with 3B active parameters and a 524K context window. It is built for agentic use cases where response...

Three real jobs, priced on this model

Each figure is derived from the prices above and moves when they do.

JobTokensCost
One chat turn with a medium history1,500 in + 400 out54 toman
Summarising a ten-page document4,000 in + 600 out111 toman
Classifying a thousand short rows120,000 in + 20,000 out3,462 toman

Frequently asked

How do I call Solar Mini 4 from Iran?
Sign up with your mobile number, top the wallet up in toman, create an API key, then in the official OpenAI SDK point base_url at https://api.uttapen.ir/v1 and set model to "upstage/solar-mini4". Nothing else in your code changes.
What does Solar Mini 4 cost in toman?
17,311 toman per 1M input tokens and 69,244 toman per 1M output tokens; a 1,000-word request is around 113 toman. You pay for the usage that request actually reported, and a failed request costs nothing.
How much input does Solar Mini 4 take?
Up to 524,288 tokens per request, roughly 393k words. A single answer can reach 131,072 tokens.
Does Solar Mini 4 support streaming and tool calling?
Streaming (stream=true) works on every model here. This one supports tool calling in the standard OpenAI shape. Structured output through response_format works too.