GPT-5.1 vs Sonar Reasoning Pro
At a Glance
| Compare |  GPT-5.1OpenAI |  Sonar Reasoning ProPerplexity |
|---|---|---|
| Intelligence, Cost, and Efficiency | ||
| IntelligenceHigher is better · MM Intelligence v2.5 | #37 of 4625.7 score · 2/3 sources · provisional · missing LiveBench · full-core range 17.1–50.5 | UnrankedNot in the 46-model eligible cohort |
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $1.25Openai ↗ · Sep 3, 2026 | $2.00Openrouter ↗ · Sep 22, 2026 |
| Output priceFrom · USD / 1M tokens | $10.00Openai ↗ · Sep 3, 2026 | $8.00Openrouter ↗ · Sep 22, 2026 |
| Context windowMaximum documented tokens | 400K | 128K |
| Model facts checked | Sep 3, 2026View model evidence → | Aug 29, 2026View model evidence → |
Token prices are the lowest available sourced USD rates; input and output may use different providers. Cost ranking estimates output spend on LiveBench, not a full request bill. Ranking methodology →
Available Benchmarks
| Benchmark | GPT-5.1 | Sonar Reasoning Pro |
|---|---|---|
| LMArena Search Arenasearch-2026-08-24-d25aabda0010 · arena_rating · leader | 1,199.44100% of row best · rating · gpt-5.1-search; 95% CI [1194.20592738, 1204.68165473]; votes 59909; rank 14 | 1,138.6095% of row best · rating · ppl-sonar-reasoning-pro-high; 95% CI [1132.86119454, 1144.34164089]; votes 29055; rank 29 |
| Overall ResultCounted from the protocol-matched rows above | 1 benchmark winNo overall winner | 0 benchmark winsNo overall winner |
Third-party benchmark Only like-for-like primary-publisher results are shown; raw scores, relative scores, configuration, and token spend remain visible.
Side-by-Side Facts
| Field | GPT-5.1 | Sonar Reasoning Pro |
|---|---|---|
| Developer | OpenAI | Perplexity |
| Family | Gpt 5 1 | Sonar |
| Model | GPT-5.1 | Sonar Reasoning Pro |
| Version | GPT-5.1 | Sonar Reasoning Pro |
| Lifecycle | active | active |
| Released | 2025-11-13 | Unknown |
| Knowledge cutoff | 2024-09-30 | Unknown |
| Input modalities | Text, Image | Text |
| Output modalities | Text | Text |
| Context window | 400K | 128K |
| Total parameters | Unknown | Unknown |
| Active parameters | Unknown | Unknown |
| License | Unknown | Unknown |
| Open weights | No | No |
| API available | Yes | Yes |
| Self-hostable | No | No |
| Provider access | Openai (Standard), Openrouter (Standard) | Openrouter (Standard), Perplexity (Standard) |
| Capabilities | chat, generation, reasoning, structured_outputs, tools | chat, citations, reasoning, search |
GPT-5.1 Capabilities
Sonar Reasoning Pro Capabilities
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Primary Evidence
Sources and Freshness
Questions
GPT-5.1 vs Sonar Reasoning Pro FAQs
Is GPT-5.1 or Sonar Reasoning Pro better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both GPT-5.1 and Sonar Reasoning Pro, so Model Markets cannot name a coding leader from pricing, context size, or capability labels alone.
Which is cheaper, GPT-5.1 or Sonar Reasoning Pro?+
GPT-5.1 is $1.25 and Sonar Reasoning Pro is $2.00 per million tokens, so GPT-5.1 is cheaper on this metric. GPT-5.1 is $10.00 and Sonar Reasoning Pro is $8.00 per million tokens, so Sonar Reasoning Pro is cheaper on this metric.
Which has a larger context window, GPT-5.1 or Sonar Reasoning Pro?+
GPT-5.1 has the larger sourced context window. GPT-5.1 supports 400K and Sonar Reasoning Pro supports 128K.
Which performs better in benchmarks, GPT-5.1 or Sonar Reasoning Pro?+
There is no overall benchmark winner: At least two independently verified, protocol-matched benchmarks are required for an overall winner.
Can GPT-5.1 or Sonar Reasoning Pro be self-hosted?+
Both models have the same recorded self-hosting status: unsupported. GPT-5.1 is not marked open weight; Sonar Reasoning Pro is not marked open weight.
Can GPT-5.1 and Sonar Reasoning Pro understand images?+
GPT-5.1 is documented with image input; Sonar Reasoning Pro is not documented with image input. This reflects supported input modalities, not vision quality.
Which can generate longer answers, GPT-5.1 or Sonar Reasoning Pro?+
Neither has a larger sourced maximum output. GPT-5.1 is 128K and Sonar Reasoning Pro is —.
Do GPT-5.1 and Sonar Reasoning Pro support reasoning and tool use?+
GPT-5.1: reasoning, tool calling, and image input. Sonar Reasoning Pro: reasoning. Feature support does not establish relative quality.
Which is available from more inference providers, GPT-5.1 or Sonar Reasoning Pro?+
GPT-5.1 has 2 sourced provider routes; Sonar Reasoning Pro has 2, a tie.
Which offers better value, GPT-5.1 or Sonar Reasoning Pro?+
There is no universal value winner. Compare the input and output prices above with the matched benchmark result for your workload: cheaper tokens can be offset by different quality, token usage, latency, or provider availability.