Skip to content
ModelCap

GPT-5.1

All-versions archive #45Arena #77API only

OpenAI·openai/gpt-5.1

GPT-5.1 is a language model published by OpenAI. 5 OpenRouter endpoints are published in the latest snapshot. It accepts image, text, file input and returns text. The published context limit is 400K tokens. The catalogue declares support for reasoning, tool use, structured outputs.

ModelCap Index · All-versions archive
75.1#45
Measured · 86% support · score interval 75.1–81.3
Market Gravity
38.1
Secondary market signal

Superseded by GPT-5.5. It no longer holds a current-board position; its all-versions archive rank is #45.

Input
$1.25
per 1M tokens
Output
$10.00
per 1M tokens
Context
400K
tokens
Providers
5
endpoints
Gateway spend
—
latest · Vercel share

Providers

Uptime measured over the last 30 minutes
ProviderInputOutputContextQuantUptime
OpenAIdefault/flexCheapest$0.625$5.00400K—99.49%
OpenAIdefault$1.25$10.00400K—99.49%
Azure$1.25$10.00400K—100.0%
Azureswedencentral$1.38$11.00400K——
OpenAIdefault/priority$2.50$20.00400K—99.49%

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.

Related community configurations

Human preference rating
ConfigurationRatingSource rankVotesSource
High
gpt-5.1-high
1454
CI 1451–1458
#5641KArena
Match 100%

Other versions (6)

ModelCap Index · All-versions archive

Methodology
75.1
Measured · 3 public benchmark observations across 3 boards
All-versions archive
#45
Public rank basis
Measured (measured)
Index support
85.8% · strong
Index interval
75.1–81.3
Rank posterior
Not available
Top 5 / Top 10 probability
Not available / Not available
Posterior as of
Snapshot timestamp unavailable
Identity binding
Exact catalogue product · openai/openai/gpt-5.1 · aggregates disclosed benchmark configurations · endpoint configuration not claimed
Direct benchmark observations
3
Breadth-adjusted BES point estimate
78.2
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
78.2
Evidence status
confirmed · 93% mass
General preference
79.1
Coding
80.4
Agents & tools
—
Reasoning
50.5
Evidence breadth
95%
Evidence coverage
86%
Market and catalogue signals · secondary, never the language Index rank
Usage (OpenRouter popularity)
17.8
Liquidity (providers × uptime)
76.1
Open reach (HF downloads)
—
Surface (context / tools / modalities)
93.3
Freshness
36.2
  • · OpenRouter popularity #108
  • · 2 live providers
  • · Catalogue: context 400000, reasoning, tools, modalities Image/Text/File
  • · First seen 2025-11-13

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
48.4
partial · 56% metadata coverage
Not capability
Artifact reproducibility
0.0
Access & legal clarity
30.3
Deployability
90.0
Evaluation provenance
76.5

Missing: artifactReproducibility.revision-sha, artifactReproducibility.architecture-and-model-type, artifactReproducibility.parameter-count, artifactReproducibility.serialized-weight-format, artifactReproducibility.base-lineage, accessLegalClarity.declared-license, accessLegalClarity.resolvable-license-terms, evaluationProvenance.evaluation-dataset-revisions.

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

Market activity

Venue coverage
Market Gravity
38.1
OpenRouter weekly popularity
#108 of 298

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
Arena
Official rank
#77 of 385
Rating
1438.6
95% confidence interval
1435–1442
Votes
43K
Source snapshot
6 Aug 2026, 13:00 UTC
Category
overall
Identity match confidence
100%

Market Gravity breakdown

Usage55%
17.8

OpenRouter weekly popularity across the full model catalogue.

Liquidity25%
76.1

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%
36.2

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

Specification

Context window
400K tokens
Max output
128K tokens
Inputs
Image, Text, File
Outputs
Text
Tokenizer
GPT
Cached input tokens
$0.125 / 1M
First seen on OpenRouter
13 Nov 2025

Capabilities

  • Supported: Reasoning
  • Supported: Tool use
  • Supported: Structured output
  • Supported: Response format
  • Supported: Moderated