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ModelCap

Solar Pro 4

Arena #177API only

Upstage·#113 of 274 on the current board·cheaper than #112 GLM 4.6V

Solar Pro 4 is a language model from Upstage. It ranks #113 of 274 on ModelCap's current board, with an Index score of 51.0, measured on 3 public benchmarks. Its score range of 44.5–57.5 spans positions #87–#135. It is listed at $0.09 per million input tokens and $0.36 per million output tokens from one provider. It reads up to 524K tokens of context and is available only through an API.

Figures as of 25 Sept 2026, 03:53 UTC · download the public dataset · methodology

ModelCap Index · Current board
51.0#113
Measured on 3 public benchmarks · range 44.5–57.5
Evidence as of 24 Sept 2026, 00:00 UTC
Market Gravity
50.0
Secondary market signal
Input
$0.09
per 1M tokens
Output
$0.36
per 1M tokens
Context
524K
tokens
Providers
1
2 endpoints

Providers

Uptime measured over the last 30 minutes
ProviderInputOutputContextQuantUptime
UpstagezdrCheapest$0.09$0.36524K—100.0%
Upstage$0.09$0.36524K—100.0%

Reasoning efforts

Best supported result can inform ModelCap

Published Max, X-High, High and other configurations for this model. These are sourced scores, not head-to-head essays.

EffortAgent scoreSource rankSampleSource
Default
Solar Pro 4
-16.38%
CI -18.2–-14.5%
#43373K obs
9K sessions
LMArena Agent
Match 100%

Other versions (1)

ModelCap Index · Current board

Methodology
51.0
Measured on 3 public benchmarks
Current board
#113 of 274
Score range
44.5–57.5
Rank range
#87–#135
Evidence as of
24 Sept 2026, 00:00 UTC
Benchmarks used
Arena Coding, Arena Overall, LMArena Agent
Technical details
Public rank basis
Measured (measured)
Evidence label
Measured · 3 public benchmark observations across 3 boards
Index support
43.4% · moderate
Identity binding
Exact catalogue product · upstage/upstage/solar-pro4 · aggregates disclosed benchmark configurations · endpoint configuration not claimed
Index observations used
3
Qualified Index evidence point
51.0
Bayesian Evidence Score · measured evidence input only

BES normalizes admitted public benchmark evidence for measured Index rows. Its legacy score and observables prior do not define the public language rank.

Observed capability
51.0
Evidence status
confirmed · 81% mass
General preference
51.4
Coding
58.5
Agents & tools
14.5
Reasoning
—
Evidence breadth
97%
Evidence coverage
43%
Market and catalogue signals · secondary, never the language Index rank
Usage (OpenRouter popularity)
53.4
Liquidity (providers × uptime)
35.7
Open reach (HF downloads)
—
Surface (context / tools / modalities)
80.3
Freshness
84.1
  • · OpenRouter popularity #15
  • · 1 live provider
  • · Catalogue: context 524288, reasoning, tools
  • · First seen 2026-08-10

These adoption and deployment observations remain context only. They do not change this model's ModelCap Index score or rank.

BES evidence selected · measured input only

The bounded 0–100 capability score blends each source’s competitive placement with its published achievement, then combines capability families. Evidence breadth adds a modest uncertainty adjustment; price and popularity are not part of benchmark-led rank.

Deployment readiness

Metadata index
44.5
limited · 56% metadata coverage
Not capability
Artifact reproducibility
0.0
Access & legal clarity
30.3
Deployability
80.0
Evaluation provenance
72.0

Not yet published: a pinned repository revision, the architecture and model type, a parameter count, safetensors weight metadata, the base model it derives from, a declared licence, a link to the licence terms, pinned evaluation dataset versions.

A metadata completeness and deployability index—not a safety certification, quality grade, or production-readiness claim.

Market activity

Venue coverage
Market Gravity
50.0
OpenRouter weekly popularity
#15 of 335

Market Gravity uses OpenRouter’s full-catalogue popularity order. Sparse Vercel top-ten observations appear only when published and do not affect the score.

Arena preference

Status
Ranked
Source
LMArena
Official rank
#177 of 402
Rating
1376.4
95% confidence interval
1364–1389
Votes
2K
Source published at
13 Sept 2026, 00:00 UTC
Category
overall
Identity match confidence
99%

Market Gravity breakdown

Usage55%
53.4

OpenRouter weekly popularity across the full model catalogue.

Liquidity25%
35.7

Independent providers versus the model's open or closed cohort, weighted by uptime.

Open reach15%
50.0

Hugging Face 30-day downloads for open models; neutral for closed models.

Freshness5%
84.1

Time since first public availability, on a six-month half-life.

Specification

Model ID
upstage/solar-pro4
Context window
524K tokens
Max output
131K tokens
Inputs
Text
Outputs
Text
Tokenizer
Other
Cached input tokens
$0.018 / 1M
First seen on OpenRouter
10 Aug 2026

Capabilities

  • Supported: Reasoning
  • Supported: Tool use
  • Supported: Structured output
  • Supported: Response format
  • Not supported: Moderated

Benchmark leaderboards featuring Solar Pro 4

All leaderboards
Public benchmark boards on which Solar Pro 4 has a published result
LeaderboardScoreSource rankConfigurationPublished
Arena coding leaderboardArena (LMArena)14491426–1472#144 of 397Default13 Sept 2026
LMArena Agent leaderboardLMArena-16.4%-18.2%–-14.5%#43 of 43Default24 Sept 2026
Humanity's Last Exam (Artificial Analysis run)Artificial Analysis29.2%#133 of 632Reasoning5 Sept 2026

Alternatives to Solar Pro 4, by the numbers

Ranked neighbours

Models within 3 places of #113 on the ModelCap Index.

Cheaper at a similar or higher Index

Index score within 3 points of, or above, this model's, with a lower listed blended price (3:1 input:output).

Other ranked Upstage models

The same publisher's other current models with a public Index position.

Solar Pro 4: common questions

How does Solar Pro 4 rank among AI models?

Solar Pro 4 holds ModelCap Index position #113 of 274 ranked language models as of 25 September 2026, with an Index score of 51.0 (interval 44.5–57.5); evidence: measured. The Index combines public benchmark boards with published uncertainty; the methodology page explains the weighting.

How much does Solar Pro 4 cost per 1M tokens?

Solar Pro 4 is listed at $0.09 per 1M input tokens and $0.36 per 1M output tokens as of 25 September 2026. Prices come from the OpenRouter catalogue and re-observe on every refresh. For 1,000 requests using 2,000 input and 500 output tokens each, the listed rates imply $0.36 total (2M input + 0.5M output). This excludes caching, batch discounts, prompt-length tiers, tool charges and retries; verify the chosen endpoint's rate and limits before budgeting.

What is the context window of Solar Pro 4?

Solar Pro 4 has a published context window of 524K tokens (524,288) and a maximum output of 131K tokens. Individual providers can serve less than the published maximum; the providers table lists each endpoint's own limit.

Is Solar Pro 4 open-weight?

API only. No downloadable model weights are linked in the current source data; access is through a hosted API or product.

Which API providers serve Solar Pro 4?

One provider serves Solar Pro 4 through OpenRouter as of 25 September 2026: Upstage. Each provider's price, context limit, quantization and measured uptime are in the providers table above.

Which benchmarks has Solar Pro 4 been evaluated on?

Solar Pro 4 has published results on 3 public boards tracked by ModelCap as of 25 September 2026: Arena coding 1449 (#144 of 397), LMArena Agent -16.4% (#43 of 43) and AA Humanity's Last Exam 29.2% (#133 of 632). Each board page ranks every tracked model on that benchmark. The ModelCap Index scores the results its methodology admits, with published uncertainty, and shows reference boards without scoring them.

When was Solar Pro 4 released?

Solar Pro 4 first appeared in the catalogue on 10 Aug 2026. It is the current version in its family. Rank and price movements since then are recorded on the site's changes feed.