UpstageFastReleased 23 September 2026
Solar Mini 4 pricing, context and benchmark
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.
524K
Input context
131K
Output context
$0.05
Official input
$0.2
Official output
n/a
AA index
01 · Model Overview
Everything that matters, in one table
Context, pricing, cache, modalities and tooling, from the model registry and Artificial Analysis.
| Model | Solar Mini 4 |
| Model ID | upstage/solar-mini4 |
| Provider | Upstage |
| Release date | 23 September 2026 |
| Status | Generally available |
| Input context | 524,288 tokens |
| Output context | 131,072 tokens |
| Official input pricing | $0.05 per 1M tokens |
| Official output pricing | $0.2 per 1M tokens |
| Cache read pricing | Not published |
| Market input pricing | $0.05 per 1M (cheapest route) |
| Market output pricing | $0.2 per 1M (cheapest route) |
| Input modalities | text |
| Output modalities | text |
| Reasoning control | Not exposed |
| Tool support | Text generation only |
| Tokenizer | Other |
| Provider routes | 2 endpoints |
| Artificial Analysis index | Not published |
| Speed | Not published |
| Knowledge cutoff | Not publicly stated |
Input and output support
| Modality | Input | Output | Billed at |
|---|---|---|---|
| Text | ✓ yes | ✓ yes | $0.05 in |
| Image | no | no | not supported |
| Audio | no | no | not supported |
| Video | no | no | not supported |
| File (PDF) | no | no | not supported |
02 · Overview
What is Solar Mini 4?
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...
Solar Mini 4 carries a 524K token window, uses the Other tokenizer and is served by Upstage. On Hoodgen it sits in the Fast tier of the model menu next to its siblings, so you can switch mid conversation without losing the thread.
03 · Release
Release and what changed from the previous version
Released23 September 2026
| Property | Solar Pro 4 | Solar Mini 4 | Change |
|---|---|---|---|
| Released | 2026 | Sep 2026 | Newer release |
| Context | 524K | 524K | Unchanged |
| Max output | 131K | 131K | Unchanged |
| Input price | $0.15 | $0.05 | Cheaper |
| Output price | $0.6 | $0.2 | Cheaper |
| Input modalities | text | text | Unchanged |
| AA index | n/a | n/a | Newer benchmark run |
07 · Use cases
What can you do with Solar Mini 4?
High volume drafts
Captions, titles, product blurbs and rewrite passes where cost per call dominates.
Inline assistants
Autocomplete, quick replies and menu helpers that must answer inside a second.
Batch classification
Tagging, routing and extraction across thousands of short inputs.
Cheap agent loops
Tool calling loops that do not need frontier grade reasoning.
09 · Pricing
Solar Mini 4 pricing
Official pricing
List price
$0.05 / 1M in
$0.2 / 1M out
- 524K context
- text input
Cheapest route
$0.05 / 1M in
$0.2 / 1M out
- 2 routes on OpenRouter
- What Hoodgen routes to first
- Same model, lower bill
Market pricing, every route
| Provider | Tier | Input | Output | Cache read | Uptime 24h |
|---|---|---|---|---|---|
| Upstage | standard | $0.05 | $0.2 | $0.005 | 100.0% |
| Upstage | standard | $0.05 | $0.2 | $0.005 | 100.0% |
API pricing and cost calculator
| Rate | Per call | Total | Credits |
|---|---|---|---|
| Cheapest route | $0.0008 | $0.38 | 361 |
| List price | $0.0013 | $0.65 | 618 |
10 · Developers
API and developer information
| Model ID | upstage/solar-mini4 |
| Endpoint | https://openrouter.ai/api/v1/chat/completions |
| Parameters | prompt and max_tokens |
| Streaming | Yes, server sent events |
| Modality string | text->text |
| Max prompt tokens | 524,288 |
| Max completion tokens | 131,072 |
curl https://openrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $OPENROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "upstage/solar-mini4",
"messages": [{ "role": "user", "content": "Summarise this document." }],
"max_tokens": 1024
}'11 · Limitations
Model limitations
| Text only output | It cannot generate images, audio or video. Pair it with an image model on Hoodgen when you need visuals. |
| Output cap | 131,072 tokens per request. Long deliverables have to be chunked. |
| Benchmarks not published | Artificial Analysis does not publish an Intelligence Index for this release, so no benchmark score is claimed here. |
| Knowledge cutoff | The provider does not state a fixed cutoff for every release. Verify very recent events against search. |
| Depth ceiling | Fast tier: strong on throughput, weaker than flagship tiers on long multi step reasoning. |
12 · Comparison
Solar Mini 4 vs other Upstage models
| Model | Context | Input /1M | Output /1M | AA index | Released |
|---|---|---|---|---|---|
| Solar Mini 4 | 524K | $0.05 | $0.2 | n/a | Sep 2026 |
| Solar Pro 4 | 524K | $0.15 | $0.6 | n/a | 2026 |
13 · Privacy
Privacy and data policy
- On Hoodgen, prompts and attachments answer that request and stay in your conversation history so you can reopen it. They are not used to train models.
- Requests route through OpenRouter to Upstage and are covered by that provider's API terms.
- Do not paste secrets or personal data you would not send to any hosted model.
14 · FAQ
Solar Mini 4 questions, answered
Solar Mini 4 is a fast model from Upstage, released 23 September 2026. 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.
✦
Start chatting with Solar Mini 4
Free to try on Hoodgen AI, with a live credit estimate before every send. No API key, no setup.