LLM Reference

Claude Mythos 5 vs DeepSeek V4 Flash

Claude Mythos 5 (2026) and DeepSeek V4 Flash (2026) are frontier-tier reasoning models from Anthropic and DeepSeek. Claude Mythos 5 ships a 1m-token context window, while DeepSeek V4 Flash ships a 1m-token context window. On pricing, DeepSeek V4 Flash costs $0.10/1M input tokens versus $10/1M 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 Flash is ~10073% cheaper at $0.10/1M; pay for Claude Mythos 5 only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude Mythos 5DeepSeek V4 Flash
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$50/1M tokens$0.20/1M tokens
Provider routes3 tracked5 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Claude Mythos 5 when...
  • Claude Mythos 5 uniquely exposes Vision, Multimodal, and Code execution in local model data.
  • Local decision data tags Claude Mythos 5 for Coding, RAG, and Agents.
Choose DeepSeek V4 Flash when...
  • DeepSeek V4 Flash has the lower cheapest tracked output price at $0.20/1M tokens.
  • DeepSeek V4 Flash has broader tracked provider coverage for fallback and procurement flexibility.
  • Local decision data tags DeepSeek V4 Flash 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 Flash

Claude Mythos 5

$20,500

Cheapest tracked route/tier: Anthropic

DeepSeek V4 Flash

$128

Cheapest tracked route/tier: OpenRouter

Estimated monthly gap: $20,372. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Mythos 5 -> DeepSeek V4 Flash
  • No overlapping tracked provider route is sourced for Claude Mythos 5 and DeepSeek V4 Flash; plan for SDK, billing, or endpoint changes.
  • DeepSeek V4 Flash is $49.80/1M 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 Flash -> Claude Mythos 5
  • No overlapping tracked provider route is sourced for DeepSeek V4 Flash and Claude Mythos 5; plan for SDK, billing, or endpoint changes.
  • Claude Mythos 5 is $49.80/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
  • Claude Mythos 5 adds Vision, Multimodal, and Code execution in local capability data.

Specs

Specification
Released2026-06-092026-04-24
Context window1m1m
Parameters284B
ArchitectureDecoder OnlyMixture of Experts
LicenseProprietaryMITOSI-approved
OpennessProprietaryOpen source
Commercial useCommercial use: conditionalCommercial use: permitted
Knowledge cutoff--

Pricing and availability

Pricing attributeClaude Mythos 5DeepSeek V4 Flash
Input price$10/1M tokens$0.10/1M tokens
Output price$50/1M tokens$0.20/1M tokens
Providers

Capabilities

CapabilityClaude Mythos 5DeepSeek V4 Flash
VisionYesNo
MultimodalYesNo
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesNo
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint differs most on vision: Claude Mythos 5, multimodal input: Claude Mythos 5, and code execution: Claude Mythos 5. Both models share reasoning mode, function calling, tool use, and structured outputs, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, Claude Mythos 5 lists $10/1M input and $50/1M output tokens on the cheapest tracked provider, while DeepSeek V4 Flash lists $0.10/1M input and $0.20/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts DeepSeek V4 Flash lower by about $21.87 per million blended tokens. Availability is 3 providers versus 5, so concentration risk also matters.

Choose Claude Mythos 5 when coding workflow support are central to the workload. Choose DeepSeek V4 Flash when provider fit, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions.

FAQ

Which has a larger context window, Claude Mythos 5 or DeepSeek V4 Flash?

Claude Mythos 5 supports 1m tokens, while DeepSeek V4 Flash supports 1m tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Claude Mythos 5 or DeepSeek V4 Flash?

DeepSeek V4 Flash is cheaper on tracked token pricing. Claude Mythos 5 costs $10/1M input and $50/1M output tokens. DeepSeek V4 Flash costs $0.10/1M input and $0.20/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Claude Mythos 5 or DeepSeek V4 Flash open source?

Claude Mythos 5 is listed under Proprietary. DeepSeek V4 Flash is listed under MIT. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, Claude Mythos 5 or DeepSeek V4 Flash?

Claude Mythos 5 has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Which is better for multimodal input, Claude Mythos 5 or DeepSeek V4 Flash?

Claude Mythos 5 has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.

Where can I run Claude Mythos 5 and DeepSeek V4 Flash?

Claude Mythos 5 is available on Anthropic, AWS Bedrock, and GCP Vertex AI. DeepSeek V4 Flash is available on DeepSeek Platform, OpenRouter, Microsoft Foundry, Vercel AI Gateway, and Novita AI. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.