Claude Mythos Preview vs Claude Sonnet 4.6

Claude Mythos Preview (2026) and Claude Sonnet 4.6 (2026) are frontier-tier reasoning models from Anthropic. Both ship a 1m-token context window. On SWE-bench Verified, Claude Mythos Preview leads by 14.3 pts. On pricing, Claude Sonnet 4.6 costs $3/1M input tokens versus $25/1M for the alternative. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Claude Sonnet 4.6 is ~733% cheaper at $3/1M; pay for Claude Mythos Preview only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude Mythos PreviewClaude Sonnet 4.6
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, multimodal apps, and tool-calling agents
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1m1m
Cheapest output$125/1M tokens$15/1M tokens
Provider routes2 tracked6 tracked
Shared benchmarksSWE-bench Verified leader3 shared

Decision tradeoffs

Choose Claude Mythos Preview when...
  • Claude Mythos Preview holds a shared-benchmark lead on SWE-bench Verified, ahead by 14.3 points.
  • Local decision data tags Claude Mythos Preview for Coding, RAG, and Agents.
Choose Claude Sonnet 4.6 when...
  • Claude Sonnet 4.6 has the lower cheapest tracked output price at $15/1M tokens.
  • Claude Sonnet 4.6 has broader tracked provider coverage for fallback and route flexibility.
  • Claude Sonnet 4.6 uniquely exposes Computer use and Parallel agents in local model data.
  • Local decision data tags Claude Sonnet 4.6 for Coding, RAG, and Agents.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Claude Sonnet 4.6

Claude Mythos Preview

$51,250

Cheapest tracked route/tier: Anthropic

Claude Sonnet 4.6

$6,150

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $45,100. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Mythos Preview -> Claude Sonnet 4.6
  • Provider overlap exists on Anthropic and Microsoft Foundry; start route-level A/B tests there.
  • Claude Sonnet 4.6 is $110/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Claude Sonnet 4.6 adds Computer use and Parallel agents in local capability data.
Claude Sonnet 4.6 -> Claude Mythos Preview
  • Provider overlap exists on Anthropic and Microsoft Foundry; start route-level A/B tests there.
  • Claude Mythos Preview is $110/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Check replacement coverage for Computer use and Parallel agents before moving production traffic.

Specs

Specification
Released2026-05-012026-02-17
Context window1m1m
Parameters——
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
WeightsNot releasedNot released
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff2025-122025-08

Pricing and availability

Pricing attributeClaude Mythos PreviewClaude Sonnet 4.6
Input price$25/1M tokens$3/1M tokens
Output price$125/1M tokens$15/1M tokens
Providers
AnthropicMicrosoft Foundry
OpenRouterAnthropicAWS BedrockGCP Vertex AIMicrosoft FoundryVercel AI Gateway

Capabilities

CapabilityClaude Mythos PreviewClaude Sonnet 4.6
VisionYesYes
MultimodalYesYes
ReasoningYesYes
JSON / Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoYes
Parallel agentsNoYes

Benchmarks

BenchmarkClaude Mythos PreviewClaude Sonnet 4.6
SWE-bench Verified93.979.6
Google-Proof Q&A94.689.9
τ-bench89.287.5

Continue comparing

Model pages
Labs and families
Related comparisons

Popular comparisons for Claude Mythos Preview

Popular comparisons for Claude Sonnet 4.6

Last reviewed: 2026-07-26. Data sourced from public model cards and provider documentation.