MODEL PROOF
GPT-5.1
BETTER VALUE OPTION
A stored alternative has an equal-or-higher measured score and an equal-or-lower price.
Muse Spark 1.3 · Δ score 67.7 points · 42% lower measured price · $2.00 / 1M tokens
MiMo-V2.6-Pro is a further stored option with these losses: no file input
- Independent LMArena score
- 1,422.2 ± 3.56 · 44,298 votes
- Context window
- 400K
- Maximum output
- 128K
- Input modalities
- image, text, file
- 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 OpenAI: the cheapest offer that is serving, at standard delivery and at the maker’s precision or better, at its standard rate.
Cheaper right now: $1.72/M at OpenAI — delivery tier (flex) It does not pass the like-for-like test, so it never sets a rank.
Every price dimension · USD per million tokens
| Input | $1.25/M |
|---|---|
| Output | $10.00/M |
| Cached input | $0.125/M |
| Cache write | Unknown/M |
| Cache write 1h | Unknown/M |
| Reasoning | Unknown/M |
| Web search | $0.01/call |
Who sells it
The same weights, different shops. Cheapest is not like-for-like when serving precision differs.
5 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.
| Seller | Input | Output | Precision | Uptime (1d) |
|---|---|---|---|---|
| OpenAIopenai/flex Endpoint terms
| $0.625 | $5.00 | undeclared | 99.98% |
| Azureazure Endpoint terms
| $1.25 | $10.00 | undeclared | 99.57% |
| OpenAIopenai Endpoint terms
| $1.25 | $10.00 | undeclared | 99.98% |
| Azureazure/swedencentral Endpoint terms
| $1.38 | $11.00 | undeclared | 100.00% |
| OpenAIopenai/fast Endpoint terms
| $2.50 | $20.00 | undeclared | 100.00% |
Independent scores
| LMArena Elo | 1422.2default |
|---|
LMArena Elo under CC BY 4.0. Absence of another board is not a score of zero.
Best rankings by task
- SVG #45 1148
- Data visualisation #48 1213
- Game development #53 1191
- ASCII art #54 1129
- Websites #63 1193
- Code categories #64 1175
- UI components #64 1173
- 3D #93 1069
Per-task Elo and rank from Design Arena, via OpenRouter’s model feed. The rank is the feed’s, and it counts models OpenRouter does not list.
Capability
| Context window | 400K |
|---|---|
| Max output | 128K |
| Input modes | image, text, file |
| Tool use | yes |
| Reasoning | optional |
| Open weights | no |
Provenance
| Price source | openrouter.ai |
|---|---|
| Fetched | 2026-10-06 |
| Quality data | verified |
People search GPT-5.1 cost. This is the GPT-5.1 API row, not Codex Max and not a ChatGPT subscription. Codex SKUs are listed on the GPT-5.1 family page.
GPT-5.1 is the latest frontier-grade model in the GPT-5 series, offering stronger general-purpose reasoning, improved instruction adherence, and a more natural conversational style compared to GPT-5. It uses adaptive reasoning...
Questions this page answers
What does GPT-5.1 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 have an independent quality score?
GPT-5.1 has an LMArena score in this catalogue.
What beats GPT-5.1?
Muse Spark 1.3 has an equal-or-higher measured score and an equal-or-lower price.
Does this page use Artificial Analysis scores for GPT-5.1?
No. Artificial Analysis figures are not published here. Quality on this page is LMArena Elo where a score exists; otherwise the row is unrated.
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.
[](https://undominated.ai/models/openai__gpt-5.1/)<a href="https://undominated.ai/models/openai__gpt-5.1/"><img src="https://undominated.ai/badge/openai__gpt-5.1.svg" alt="GPT-5.1 — Undominated.ai dominance verdict" height="36"></a>Direct file: https://undominated.ai/badge/openai__gpt-5.1.svg — a static SVG, written by scripts/build-badges.mjs on every build, so the copy you embed is never
older than the last deploy.
