LLM Reference

Claude Mythos 5 vs GPT-5.2

Claude Mythos 5 (2026) and GPT-5.2 (2025) are frontier-tier reasoning models from Anthropic and OpenAI. Claude Mythos 5 ships a 1m-token context window, while GPT-5.2 ships a 400k-token context window. On pricing, GPT-5.2 costs $1.75/1M 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.

GPT-5.2 is ~471% cheaper at $1.75/1M; pay for Claude Mythos 5 only for coding workflow support.

Decision scorecard

Local evidence first
SignalClaude Mythos 5GPT-5.2
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 window1m400k
Cheapest output$50/1M tokens$14/1M tokens
Provider routes3 tracked3 tracked
Shared benchmarks0 shared0 shared

Decision tradeoffs

Choose Claude Mythos 5 when...
  • Claude Mythos 5 has the larger context window for long prompts, retrieval packs, or transcript analysis.
  • Local decision data tags Claude Mythos 5 for Coding, RAG, and Agents.
Choose GPT-5.2 when...
  • GPT-5.2 has the lower cheapest tracked output price at $14/1M tokens.
  • Local decision data tags GPT-5.2 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 GPT-5.2

Claude Mythos 5

$20,500

Cheapest tracked route/tier: Anthropic

GPT-5.2

$4,900

Cheapest tracked route/tier: Replicate API

Estimated monthly gap: $15,600. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Claude Mythos 5 -> GPT-5.2
  • No overlapping tracked provider route is sourced for Claude Mythos 5 and GPT-5.2; plan for SDK, billing, or endpoint changes.
  • GPT-5.2 is $36/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
GPT-5.2 -> Claude Mythos 5
  • No overlapping tracked provider route is sourced for GPT-5.2 and Claude Mythos 5; plan for SDK, billing, or endpoint changes.
  • Claude Mythos 5 is $36/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.

Specs

Specification
Released2026-06-092025-12-11
Context window1m400k
Parameters
ArchitectureDecoder OnlyDecoder Only
LicenseProprietaryProprietary
OpennessProprietaryProprietary
Commercial useCommercial use: conditionalCommercial use: conditional
Knowledge cutoff-2025-08

Pricing and availability

Pricing attributeClaude Mythos 5GPT-5.2
Input price$10/1M tokens$1.75/1M tokens
Output price$50/1M tokens$14/1M tokens
Providers

Capabilities

CapabilityClaude Mythos 5GPT-5.2
VisionYesYes
MultimodalYesYes
ReasoningYesYes
Function callingYesYes
Tool useYesYes
Structured outputsYesYes
Code executionYesYes
IDE integrationNoNo
Computer useNoNo
Parallel agentsNoNo

Benchmarks

No shared benchmark scores are currently available for this pair.

Deep dive

The capability footprint is close: both models cover vision, multimodal input, reasoning mode, function calling, and tool use. That makes context budget, benchmark fit, and provider maturity more important than a simple checklist. If your application depends on one integration detail, verify it against the provider route you plan to use, not just the base model listing.

For cost, Claude Mythos 5 lists $10/1M input and $50/1M output tokens on the cheapest tracked provider, while GPT-5.2 lists $1.75/1M input and $14/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts GPT-5.2 lower by about $16.57 per million blended tokens. Availability is 3 providers versus 3, so concentration risk also matters.

Choose Claude Mythos 5 when coding workflow support and larger context windows are central to the workload. Choose GPT-5.2 when coding workflow support and lower input-token cost 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. It also helps separate model capability from provider packaging, which can change cost and latency.

FAQ

Which has a larger context window, Claude Mythos 5 or GPT-5.2?

Claude Mythos 5 supports 1m tokens, while GPT-5.2 supports 400k 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 GPT-5.2?

GPT-5.2 is cheaper on tracked token pricing. Claude Mythos 5 costs $10/1M input and $50/1M output tokens. GPT-5.2 costs $1.75/1M input and $14/1M output tokens. Provider discounts or batch pricing can still change the final bill.

Is Claude Mythos 5 or GPT-5.2 open source?

Claude Mythos 5 is listed under Proprietary. GPT-5.2 is listed under Proprietary. 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 GPT-5.2?

Both Claude Mythos 5 and GPT-5.2 expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, Claude Mythos 5 or GPT-5.2?

Both Claude Mythos 5 and GPT-5.2 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Where can I run Claude Mythos 5 and GPT-5.2?

Claude Mythos 5 is available on Anthropic, AWS Bedrock, and GCP Vertex AI. GPT-5.2 is available on Replicate API, OpenRouter, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

Continue comparing

Last reviewed: 2026-06-18. Data sourced from public model cards and provider documentation.