Claude Mythos Preview vs Gemini Robotics-ER 1.6 Preview
Claude Mythos Preview (2026) and Gemini Robotics-ER 1.6 Preview (2026) are frontier-tier reasoning models from Anthropic and Google DeepMind. Claude Mythos Preview ships a 1m-token context window, while Gemini Robotics-ER 1.6 Preview ships a 128k-token context window. On pricing, Gemini Robotics-ER 1.6 Preview costs $1/1M 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.
Gemini Robotics-ER 1.6 Preview is ~2400% cheaper at $1/1M; pay for Claude Mythos Preview only for coding workflow support.
Decision scorecard
Local evidence first| Signal | Claude Mythos Preview | Gemini Robotics-ER 1.6 Preview |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | RAG, Agents, and Long context |
| Context window | 1m | 128k |
| Cheapest output | $125/1M tokens | $5/1M tokens |
| Provider routes | 2 tracked | 1 tracked |
| Shared benchmarks | 0 shared | 0 shared |
Decision tradeoffs
- Claude Mythos Preview has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Claude Mythos Preview has broader tracked provider coverage for fallback and procurement flexibility.
- Claude Mythos Preview uniquely exposes Code execution in local model data.
- Local decision data tags Claude Mythos Preview for Coding, RAG, and Agents.
- Gemini Robotics-ER 1.6 Preview has the lower cheapest tracked output price at $5/1M tokens.
- Local decision data tags Gemini Robotics-ER 1.6 Preview for RAG, Agents, and Long context.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Claude Mythos Preview
$51,250
Cheapest tracked route/tier: Anthropic
Gemini Robotics-ER 1.6 Preview
$2,050
Cheapest tracked route/tier: Google AI Studio
Estimated monthly gap: $49,200. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for Claude Mythos Preview and Gemini Robotics-ER 1.6 Preview; plan for SDK, billing, or endpoint changes.
- Gemini Robotics-ER 1.6 Preview is $120/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Check replacement coverage for Code execution before moving production traffic.
- No overlapping tracked provider route is sourced for Gemini Robotics-ER 1.6 Preview and Claude Mythos Preview; plan for SDK, billing, or endpoint changes.
- Claude Mythos Preview is $120/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Claude Mythos Preview adds Code execution in local capability data.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-05-01 | 2026-04-14 |
| Context window | 1m | 128k |
| Parameters | — | — |
| Architecture | Decoder Only | Decoder Only |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2025-12 | - |
Pricing and availability
| Pricing attribute | Claude Mythos Preview | Gemini Robotics-ER 1.6 Preview |
|---|---|---|
| Input price | $25/1M tokens | $1/1M tokens |
| Output price | $125/1M tokens | $5/1M tokens |
| Providers |
Capabilities
| Capability | Claude Mythos Preview | Gemini Robotics-ER 1.6 Preview |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | No |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
No shared benchmark scores are currently available for this pair.
Deep dive
The capability footprint differs most on code execution: Claude Mythos Preview. Both models share vision, multimodal input, reasoning mode, and function calling, 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 Preview lists $25/1M input and $125/1M output tokens on the cheapest tracked provider, while Gemini Robotics-ER 1.6 Preview lists $1/1M input and $5/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Gemini Robotics-ER 1.6 Preview lower by about $52.80 per million blended tokens. Availability is 2 providers versus 1, so concentration risk also matters.
Choose Claude Mythos Preview when coding workflow support, larger context windows, and broader provider choice are central to the workload. Choose Gemini Robotics-ER 1.6 Preview when vision-heavy evaluation 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.
FAQ
Which has a larger context window, Claude Mythos Preview or Gemini Robotics-ER 1.6 Preview?
Claude Mythos Preview supports 1m tokens, while Gemini Robotics-ER 1.6 Preview supports 128k 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 Preview or Gemini Robotics-ER 1.6 Preview?
Gemini Robotics-ER 1.6 Preview is cheaper on tracked token pricing. Claude Mythos Preview costs $25/1M input and $125/1M output tokens. Gemini Robotics-ER 1.6 Preview costs $1/1M input and $5/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is Claude Mythos Preview or Gemini Robotics-ER 1.6 Preview open source?
Claude Mythos Preview is listed under Proprietary. Gemini Robotics-ER 1.6 Preview 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 Preview or Gemini Robotics-ER 1.6 Preview?
Both Claude Mythos Preview and Gemini Robotics-ER 1.6 Preview expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for multimodal input, Claude Mythos Preview or Gemini Robotics-ER 1.6 Preview?
Both Claude Mythos Preview and Gemini Robotics-ER 1.6 Preview expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Where can I run Claude Mythos Preview and Gemini Robotics-ER 1.6 Preview?
Claude Mythos Preview is available on Anthropic and Microsoft Foundry. Gemini Robotics-ER 1.6 Preview is available on Google AI Studio. 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.