MODEL PROOF

GPT-5.1-Codex-Max

NOT INDEPENDENTLY RATED

No independent LMArena score is published for this model.

$3.44 / 1M tokens Balanced · 3 tokens in per 1 out
Independent LMArena score
Not independently rated
Context window
400K
Maximum output
128K
Input modalities
text, image
Output modalities
text
Published input price
$1.25 / 1M tokens
Published output price
$10.00 / 1M tokens
Pricing kind
fixed

Inspect complete billing conditions and endpoint terms below.

Price from Azure: the cheapest offer that is serving, at standard delivery and at the maker’s precision or better, at its standard rate.

Every price dimension · USD per million tokens
Input$1.25/M
Output$10.00/M
Cached input$0.125/M
Cache writeUnknown/M
Cache write 1hUnknown/M
ReasoningUnknown/M
Web search$0.01/call

Who sells it

The same weights, different shops. Cheapest is not like-for-like when serving precision differs.

1 provider offers · rates, limits and conditions

Rates are USD per million tokens. Endpoint terms can differ even when the quoted price and precision match. A listed parameter is a provider declaration, not a task-success test.

SellerInputOutputPrecisionUptime (1d)
Azureazure
Endpoint terms
Cached input /M
$0.125
Context limit
400,000 tokens
Output limit
128,000 tokens
Tools
Listed by endpoint
Reasoning
Listed by endpoint
Promotional discount
None reported
Uptime · last 30 minutes
Unknown
$1.25 $10.00 undeclared 100.00%

Independent scores

No independent benchmark has measured this model. Unrated is not a score of zero.

Capability

Context window400K
Max output128K
Input modestext, image
Tool useyes
Reasoningalways on
Open weightsno

Provenance

Price sourceopenrouter.ai
Fetched2026-10-06
Quality dataunrated

GPT-5.1-Codex-Max is OpenAI’s latest agentic coding model, designed for long-running, high-context software development tasks. It is based on an updated version of the 5.1 reasoning stack and trained on agentic...

Questions this page answers

What does GPT-5.1-Codex-Max cost?

$1.25/M in, $10.00/M out in this catalogue, as of the fetch date on this page. That is the API row, not a subscription.

Does GPT-5.1-Codex-Max have an independent quality score?

GPT-5.1-Codex-Max has no independent quality score in this catalogue. Unrated is not a score of zero.

What beats GPT-5.1-Codex-Max?

GPT-5.1-Codex-Max has no independent quality score. Unrated is not a score of zero.

Does this page use Artificial Analysis scores for GPT-5.1-Codex-Max?

No. Artificial Analysis figures are not published here. Quality on this page is LMArena Elo where a score exists; otherwise the row is unrated.

Does a missing score mean GPT-5.1-Codex-Max scored zero?

Unrated is not a score of zero.

MODEL MONUMENT

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The verdict as one SVG, for a README or a docs page. It states this model's dominance status at the balanced workload on the LMArena lens, with the date it was computed, and it is rebuilt with the catalogue — so it changes when the verdict changes, including to one you would rather it did not.

GPT-5.1-Codex-Max — Undominated.ai dominance verdict

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