Updated October 29, 2026. We do not rank this pair: at least one has no public score. Public scores include evidence status and uncertainty.
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. Use the documented cost, context, and runtime rows instead. 0 results are shared. Category rows resting on Estimated evidence or different benchmark sets are marked directional and do not name a winner.
Recommendations appear only when a shared evidence basis or an explicit operating constraint supports the call. Secondary and unsupported use cases stay disclosed below the initial list.
200K cached + 20K fresh input + 10K output tokens
Pareto 26.9
Pareto 26.9 has the lower estimated token cost for this stated workload. GPT-5.1 has no published cached-input rate, so cached tokens use its listed input rate.
50K fresh input + 3K output tokens
GPT-5.1
GPT-5.1 has the lower estimated token cost for this stated workload. Costs use the listed standard API rates.
Code generation, repair, and software-engineering tasks
Not enough matched evidence
Pareto 26.9 is not ranked on the public lane for coding, so no winner is named for coding.
Tool use, computer use, and multi-step task completion
Not enough matched evidence
GPT-5.1 and Pareto 26.9 are not ranked on the public lane for agentic, so no winner is named for agentic.
Prompts that approach the documented context limit
Not enough matched evidence
A complete context comparison is not sourced.
1K fresh input + 500 output tokens
No clear pick
A complete comparable API-rate estimate is not available for both models.
Choose a job from the LLM Selector's task catalog to see the category row it rests on, under the same basis rules as the table below. A directional row stays directional; choosing a job never creates a winner.
The same task catalog as the LLM Selector. Each job names the evidence surface it rests on; nothing here adds a new score.
Not comparable · BenchAlign v5.8
The coding row is not comparable on the public lane: at least one model is not measured or not ranked there.
Coding scores combine specific tasks and setups. Match the editor, harness, and effort to your workflow.
Shared results can support a head-to-head reading. Results present for only one model describe coverage, not superiority.
Only shared public evidence is shown. Sparse evidence stays a ruled list rather than being closed into a radar shape.
A shared-evidence shape is not available.
BenchLM does not draw a radar or infer missing axes when the matched evidence is too sparse.
Each row shows the public-lane category score for both models: the BenchAlign v5.8 lane for agentic, coding, and knowledge, and the weighted public rows elsewhere, with the same rank each model page reports. A row is like-for-like only when both scores rest on Supported evidence or the same weighted set. Directional and not-comparable rows remain visible, but they never receive a winner.
| Category | GPT-5.1 | Pareto 26.9 | Basis | Reading |
|---|---|---|---|---|
| Agentic | Not ranked | Not ranked | Not comparableBenchAlign v5.8 lane · 1 vs 1 public rows | Not comparable |
| Coding | 36.2Supported · #78/156 | Not ranked | Not comparableBenchAlign v5.8 lane · 1 vs 1 public rows | Not comparable |
| Reasoning | 80.0Unranked · 3 rankable rows | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Multimodal | 76.0Unranked · 1 rankable row | Not ranked | Not comparableProvisional lane · 0 vs 1 weighted rows | Not comparable |
| Knowledge | 52.3Estimated · #67/179 | Not ranked | Not comparableBenchAlign v5.8 lane · 0 vs 1 public rows | Not comparable |
| Multilingual | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Instruction following | 89.4#33/157 | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
| Math | Not ranked | Not ranked | Not comparableProvisional lane · 0 vs 0 weighted rows | Not comparable |
Ranks count the models scored in each category’s lane, so the agentic, coding, and knowledge denominators (BenchAlign v5.8) differ from the provisional-lane categories. Unranked scores sit on the provisional lane’s scale but never name a winner. Like-for-like rows within 0.5 points read as a practical tie.
Three fixed token mixes turn per-token rates into comparable decisions. Each scenario states context fit and whether cached input had to fall back to the published list-input rate.
1K fresh input + 500 output tokens
Modeled costs are equal
Costs use the listed standard API rates.
50K fresh input + 3K output tokens
GPT-5.1 has the lower modeled cost
Costs use the listed standard API rates.
200K cached + 20K fresh input + 10K output tokens
Pareto 26.9 has the lower modeled cost
GPT-5.1 has no published cached-input rate, so cached tokens use its listed input rate.
Sourced differences are shown directly. Missing facts stay explicit instead of being inferred from a model name or family.
Maximum documented context; output-token limits may be lower.
GPT-5.1
400K
Pareto 26.9
N/A
GPT-5.1
Not sourced
Pareto 26.9
pareto
Unbiased pricingA missing cached-input rate falls back to the listed input rate only in the stated workload estimate.
GPT-5.1
Not published
Pareto 26.9
$0.25 per 1M cached input tokens
Unbiased pricingGPT-5.1
Not sourced
Pareto 26.9
Not sourced
GPT-5.1
Not sourced
Pareto 26.9
Not sourced
GPT-5.1
Not sourced
Pareto 26.9
Not sourced
GPT-5.1
Reasoning
Pareto 26.9
Reasoning
GPT-5.1
Proprietary
Pareto 26.9
Proprietary
GPT-5.1
Proprietary
Pareto 26.9
Proprietary
GPT-5.1
2025-11-13
Pareto 26.9
2026-09-17
The public evidence has no benchmark result shared by both models, so it does not support a quality verdict. The page therefore keeps the decision tied to the specific documented workload.
Pareto 26.9 is not ranked on the public lane for coding, so no winner is named for coding.
GPT-5.1 and Pareto 26.9 are not ranked on the public lane for agentic tasks, so no winner is named for agentic tasks.
For the stated presets, chat costs $0.00625 on GPT-5.1 and $0.00625 on Pareto 26.9; repository review costs $0.0925 and $0.1475; the cache-heavy agent loop costs $0.375 and $0.175. GPT-5.1 has no published cached-input rate, so cached tokens use its listed input rate.
A complete documented context-window comparison is not available.
The full public result ledger is available for audit without forcing a wide desktop table onto a phone.
One weekly email when material rank, price, or benchmark evidence changes make this matchup worth revisiting.
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Last updated October 29, 2026
