llmboard.ai
Benchmarks
CompareRankings
llmboard.ai
Benchmarks
CompareRankings
HomeModelsGPT-5.1-Codex

OpenAI model product

GPT-5.1-Codex

GPT-5.1 Codex is a version of GPT-5.1 optimized for agentic coding tasks in Codex or similar environments. It features higher reasoning capabilities and is available in the Responses API. The underlying model snapshot is regularly updated.

Updated Aug 10, 2026. Default version: GPT-5.1 Codex

Compare
LLMBoard scoreN/ANot scored
CoverageN/ANo published score
Context window400KTokens
Official input priceN/AOfficial price unavailable

On this page

  • Specification
  • Capability
  • Benchmarks
  • Arena
  • Pricing
  • Versions
  • About
  • Similar models
  • FAQ

Model specification

Structured fields from the published default version.

Version
GPT-5.1 Codex
Released
Nov 19, 2025
Knowledge cutoff
Sep 30, 2024
Parameters
N/A
Context window
400K
Max output
128K
Inputs
image, text
Outputs
text
Open weights
No
License
Proprietary

Capability profile

This profile uses the latest version under this unique model that has a calculated LLMBoard score. Arena and price are excluded.

No capability profile

No published version under this unique model currently has enough benchmark coverage to calculate a score.

Benchmark results

Published benchmark records for the scored version currently unavailable.

No benchmark rows

No published benchmark result is linked to the scored version.

Arena results

Preference and agent-evaluation signals from published Arena datasets.

3 rows
Columns

Show columns

webdevwebdev-html831346.04,814N/AAug 6, 2026
webdevoverall841336.14,830N/AAug 6, 2026
webdevwebdev841336.14,830N/AAug 6, 2026

Pricing

Official vendor API PAYG pricing is summarized first. The table then lists individual provider offerings without treating their minimum as the official price.

Official API
N/A
Official provider
N/A
Lowest third-party
From $1.07 input, $8.5 output per 1M via OpenCode Zen
Tracked offerings
9
9 rows
Columns

Show columns

OpenCode Zengpt-5.1-codexglobal$1.07$8.5400KAug 7, 2026
Jiekou.AIgpt-5.1-codexglobal$1.13$9400KAug 7, 2026
Vivgridgpt-5.1-codexglobal$1.25$10400KAug 7, 2026
LLM Gatewaygpt-5.1-codexglobal$1.25$10400KAug 7, 2026
Heliconegpt-5.1-codexglobal$1.25$10400KAug 7, 2026
Abacusgpt-5.1-codexglobal$1.25$10400KAug 7, 2026
Azure Cognitive Servicesgpt-5.1-codexglobal$1.25$10400KAug 7, 2026
Azuregpt-5.1-codexglobal$1.25$10400KAug 7, 2026
AIHubMixgpt-5.1-codexglobal$1.25$10400KAug 7, 2026

Official prices use only the vendor's configured official Provider and positive standard USD PAYG rates. Third-party offers remain explicitly labeled.

GPT-5.1-Codex versions

All published versions linked to this unique model. The score columns identify the version used by the current overall ranking.

2 rows
Columns

Show columns

GPT-5.1 CodexNov 19, 2025N/AN/A400K128KNoProprietary
GPT-5.1 Codex HighNov 12, 2025N/AN/A400K128KNoProprietary

What is GPT-5.1-Codex?

A concise description based on the published model registry.

GPT-5.1 Codex is a version of GPT-5.1 optimized for agentic coding tasks in Codex or similar environments. It features higher reasoning capabilities and is available in the Responses API. The underlying model snapshot is regularly updated.

Use the benchmark, Arena and pricing sections above as separate evidence. A missing field means the current data snapshot does not support that claim.

Data snapshot: 2026-08-07. Editorial model content is not available in the backend.

Models similar to GPT-5.1-Codex

Recommendations prioritize the same model type and family, then the closest published LLMBoard score.

#164
OP

GPT-4.1-nano

OpenAI

11.4 LLMBoard

DetailsCompare
#163
OP

GPT-3.5-Turbo

OpenAI

12.5 LLMBoard

DetailsCompare
#149
OP

GPT-4.1-mini

OpenAI

22.5 LLMBoard

DetailsCompare
#141
OP

GPT-4o

OpenAI

27.9 LLMBoard

DetailsCompare
#139
OP

GPT-4.1

OpenAI

28.4 LLMBoard

DetailsCompare
#138
OP

GPT-4

OpenAI

28.5 LLMBoard

DetailsCompare

FAQ

Common questions about GPT-5.1-Codex.

When was GPT-5.1-Codex released?

GPT-5.1-Codex's default version was released on Nov 19, 2025.

How much does GPT-5.1-Codex cost?

No official standard PAYG price is currently available for GPT-5.1-Codex. The lowest tracked third-party offer starts at $1.07 input and $8.5 output via OpenCode Zen.

Who created GPT-5.1-Codex?

GPT-5.1-Codex is published under OpenAI in the model registry.

What is the context window for GPT-5.1-Codex?

The default version has a 400K token context window.

Is GPT-5.1-Codex open weight?

No. The default version is not marked as having publicly available weights.

How many API providers offer GPT-5.1-Codex?

9 published provider offerings are linked to the default version.

What models should I compare GPT-5.1-Codex with?

No nearby ranked alternatives are currently available.

Rankings

OverallCodingText ArenaPricing

Modalities

Image GenerationVideo GenerationSpeech-to-TextEmbeddings

Benchmarks

All BenchmarksReasoningMathCoding

Vendors

All VendorsOpenAIAnthropicGoogle
llmboard.aiCopyright 2026 llmboard.ai