Solar Pro 4 API

upstage/solar-pro4
Solar Pro 4 is Upstage's large language model with a 512K-token context window, built for agentic workflows, office productivity, document-intensive work, and coding.
Context
512K tokens
Input
$0.041262 / 1M tokens
Output
$0.165048 / 1M tokens
Released
Aug 10, 2026

How to use Solar Pro 4 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to upstage/solar-pro4.
import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "upstage/solar-pro4",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())
const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "upstage/solar-pro4",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());
curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"upstage/solar-pro4","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.

Solar Pro 4 API Pricing

TypePrice
Input
$0.041262 / 1M tokens
Output
$0.165048 / 1M tokens
Cached input
$0.0082524 / 1M tokens

Solar Pro 4 Benchmarks

BenchmarkScoreWhat it measuresSourceRetrieved
Intelligence
28.2
Composite score across standardised reasoning, knowledge and problem-solving evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026
Coding
52.7
Composite score across standardised coding evaluations, measured independently by Artificial AnalysisSourceSeptember 12, 2026
SWE-bench Verified
70.6
Resolving verified real GitHub issuesSourceSeptember 20, 2026

Solar Pro 4 vs other models

ModelInputOutputContextBest for
Solar Pro 4
This page
$0.041262 / 1M tokens
$0.165048 / 1M tokens
512K tokens
Agentic workflows, coding & document analysis
$6.5 / 1M tokens
$32.5 / 1M tokens
1M tokens
Complex agentic coding and enterprise workflows
$2.6 / 1M tokens
$7.8 / 1M tokens
500K tokens
Reasoning + agents with long context
$2.6 / 1M tokens
$15.6 / 1M tokens
1M tokens
Everyday coding + agents
$3.9 / 1M tokens
$19.5 / 1M tokens
1M tokens
Long-context, multimodal & agentic workflows

Frequently asked questions

Solar Pro 4 has a 524,288 tokens context window and can return up to 131,072 tokens.

Solar Pro 4 takes image, text as input and returns text.

Use upstage/solar-pro4 as the model id. Requests go to https://api.aimlapi.com/v1/chat/completions.

Solar Pro 4 became available on August 10, 2026.

Solar Pro 4 is priced at input $0.041262 / 1M tokens, output $0.165048 / 1M tokens, cached input $0.0082524 / 1M tokens.

Yes, Solar Pro 4 can stream responses as they are generated.

Yes, Solar Pro 4 accepts image input alongside text.

Solar Pro 4 was built by Upstage.

Solar Pro 4 is suited for agentic workflows, office productivity, document-intensive work, and coding.

Yes, Solar Pro 4 supports function calling, parallel tool calls, and structured outputs.

Start building with Solar Pro 4

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