Claude Mythos 5.1 vs Sonar Reasoning Pro
At a Glance
| Compare | Claude Mythos 5.1Anthropic |  Sonar Reasoning ProPerplexity |
|---|---|---|
| Pricing and Limits | ||
| Input priceFrom · USD / 1M tokens | $10.00Anthropic ↗ · Sep 2, 2026 | $2.00Openrouter ↗ · Sep 22, 2026 |
| Output priceFrom · USD / 1M tokens | $50.00Anthropic ↗ · Sep 2, 2026 | $8.00Openrouter ↗ · Sep 22, 2026 |
| Context windowMaximum documented tokens | 1,000K | 128K |
| Model facts checked | Sep 2, 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
Side-by-Side Facts
| Field | Claude Mythos 5.1 | Sonar Reasoning Pro |
|---|---|---|
| Developer | Anthropic | Perplexity |
| Family | Claude 5 1 | Sonar |
| Model | Claude Mythos 5.1 | Sonar Reasoning Pro |
| Version | Claude Mythos 5.1 | Sonar Reasoning Pro |
| Lifecycle | active | active |
| Released | 2026-09-01 | Unknown |
| Knowledge cutoff | 2026-06-01 | Unknown |
| Input modalities | Text, Image | Text |
| Output modalities | Text | Text |
| Context window | 1,000K | 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 | Anthropic (Project Glasswing) | Openrouter (Standard), Perplexity (Standard) |
| Capabilities | chat, generation, reasoning, tools | chat, citations, reasoning, search |
Claude Mythos 5.1 Capabilities
Sonar Reasoning Pro Capabilities
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Primary Evidence
Sources and Freshness
Questions
Claude Mythos 5.1 vs Sonar Reasoning Pro FAQs
Is Claude Mythos 5.1 or Sonar Reasoning Pro better for coding?+
This comparison does not currently contain a protocol-matched coding benchmark for both Claude Mythos 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, Claude Mythos 5.1 or Sonar Reasoning Pro?+
Claude Mythos 5.1 is $10.00 and Sonar Reasoning Pro is $2.00 per million tokens, so Sonar Reasoning Pro is cheaper on this metric. Claude Mythos 5.1 is $50.00 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, Claude Mythos 5.1 or Sonar Reasoning Pro?+
Claude Mythos 5.1 has the larger sourced context window. Claude Mythos 5.1 supports 1,000K and Sonar Reasoning Pro supports 128K.
Which performs better in benchmarks, Claude Mythos 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 Claude Mythos 5.1 or Sonar Reasoning Pro be self-hosted?+
Both models have the same recorded self-hosting status: unsupported. Claude Mythos 5.1 is not marked open weight; Sonar Reasoning Pro is not marked open weight.
Can Claude Mythos 5.1 and Sonar Reasoning Pro understand images?+
Claude Mythos 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, Claude Mythos 5.1 or Sonar Reasoning Pro?+
Neither has a larger sourced maximum output. Claude Mythos 5.1 is 128K and Sonar Reasoning Pro is —.
Do Claude Mythos 5.1 and Sonar Reasoning Pro support reasoning and tool use?+
Claude Mythos 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, Claude Mythos 5.1 or Sonar Reasoning Pro?+
Claude Mythos 5.1 has 1 sourced provider route; Sonar Reasoning Pro has 2, so Sonar Reasoning Pro has broader tracked availability.
Which offers better value, Claude Mythos 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.