Claude Mythos Preview vs DeepSeek V4 Pro

Claude Mythos Preview (2026) and DeepSeek V4 Pro (2026) are frontier-tier reasoning models from Anthropic and DeepSeek. Both ship a 1m-token context window. On SWE-bench Verified, Claude Mythos Preview leads by 13.3 pts. On pricing, DeepSeek V4 Pro costs $0.43/1M 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.

DeepSeek V4 Pro is ~5647% cheaper at $0.43/1M; pay for Claude Mythos Preview only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude Mythos PreviewDeepSeek V4 Pro
Best forreasoning-heavy apps, multimodal apps, and tool-calling agentsreasoning-heavy apps, tool-calling agents, and long-context analysis
Decision fitCoding, RAG, and AgentsCoding, RAG, and Agents
Context window1m1m
Cheapest output$125/1M tokens$0.87/1M tokens
Provider routes2 tracked6 tracked
Shared benchmarksSWE-bench Verified leader2 shared

Decision tradeoffs

Choose Claude Mythos Preview when...
  • Claude Mythos Preview holds a shared-benchmark lead on SWE-bench Verified, ahead by 13.3 points.
  • Claude Mythos Preview uniquely exposes Vision, Multimodal, and Code execution in local model data.
  • Local decision data tags Claude Mythos Preview for Coding, RAG, and Agents.
Choose DeepSeek V4 Pro when...
  • DeepSeek V4 Pro has the lower cheapest tracked output price at $0.87/1M tokens.
  • DeepSeek V4 Pro has broader tracked provider coverage for fallback and route flexibility.
  • Local decision data tags DeepSeek V4 Pro 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 DeepSeek V4 Pro

Claude Mythos Preview

$51,250

Cheapest tracked route/tier: Anthropic

DeepSeek V4 Pro

$566

Cheapest tracked route/tier: DeepSeek Platform

Estimated monthly gap: $50,685. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Mythos Preview -> DeepSeek V4 Pro
  • No overlapping tracked provider route is sourced for Claude Mythos Preview and DeepSeek V4 Pro; plan for SDK, billing, or endpoint changes.
  • DeepSeek V4 Pro is $124/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
  • Check replacement coverage for Vision, Multimodal, and Code execution before moving production traffic.
DeepSeek V4 Pro -> Claude Mythos Preview
  • No overlapping tracked provider route is sourced for DeepSeek V4 Pro and Claude Mythos Preview; plan for SDK, billing, or endpoint changes.
  • Claude Mythos Preview is $124/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Claude Mythos Preview adds Vision, Multimodal, and Code execution in local capability data.

Specs

Specification
Released2026-05-012026-04-24
Context window1m1m
Parameters—1.6T
ArchitectureDecoder OnlyMixture of Experts
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
WeightsNot releasedAvailable
CodeUnknownUnknown
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff2025-12-

Pricing and availability

Pricing attributeClaude Mythos PreviewDeepSeek V4 Pro
Input price$25/1M tokens$0.43/1M tokens
Output price$125/1M tokens$0.87/1M tokens
Providers

Capabilities

CapabilityClaude Mythos PreviewDeepSeek V4 Pro
VisionYesNo
MultimodalYesNo
ReasoningYesYes
JSON / Tool useYesYes
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

BenchmarkClaude Mythos PreviewDeepSeek V4 Pro
SWE-bench Verified93.980.6
Google-Proof Q&A94.690.1

Continue comparing

Last reviewed: 2026-09-24. Data sourced from public model cards and provider documentation.