Claude Sonnet 4.5 vs Gemini Robotics-ER 1.6 Preview
Claude Sonnet 4.5 (2025) and Gemini Robotics-ER 1.6 Preview (2026) are frontier-tier reasoning models from Anthropic and Google DeepMind. Claude Sonnet 4.5 ships a 200K-token context window, while Gemini Robotics-ER 1.6 Preview ships a 128K-token context window. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
Gemini Robotics-ER 1.6 Preview is safer overall; choose Claude Sonnet 4.5 when long-context analysis matters.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-09-29 | 2026-04-14 |
| Context window | 200K | 128K |
| Parameters | — | — |
| Architecture | decoder only | decoder only |
| License | Proprietary | Proprietary |
| Knowledge cutoff | 2025-12 | - |
Pricing and availability
| Pricing attribute | Claude Sonnet 4.5 | Gemini Robotics-ER 1.6 Preview |
|---|---|---|
| Input price | $3/1M tokens | - |
| Output price | $15/1M tokens | - |
| Providers | - |
Capabilities
| Capability | Claude Sonnet 4.5 | 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 | No | No |
Benchmarks
No shared benchmark rows are currently sourced 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.
Pricing coverage is uneven: Claude Sonnet 4.5 has $3/1M input tokens and Gemini Robotics-ER 1.6 Preview has no token price sourced yet. Provider availability is 7 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Claude Sonnet 4.5 when long-context analysis, larger context windows, and broader provider choice are central to the workload. Choose Gemini Robotics-ER 1.6 Preview when vision-heavy evaluation 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 Sonnet 4.5 or Gemini Robotics-ER 1.6 Preview?
Claude Sonnet 4.5 supports 200K 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.
Is Claude Sonnet 4.5 or Gemini Robotics-ER 1.6 Preview open source?
Claude Sonnet 4.5 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 Sonnet 4.5 or Gemini Robotics-ER 1.6 Preview?
Both Claude Sonnet 4.5 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 Sonnet 4.5 or Gemini Robotics-ER 1.6 Preview?
Both Claude Sonnet 4.5 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.
Which is better for reasoning mode, Claude Sonnet 4.5 or Gemini Robotics-ER 1.6 Preview?
Both Claude Sonnet 4.5 and Gemini Robotics-ER 1.6 Preview expose reasoning mode. 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 Sonnet 4.5 and Gemini Robotics-ER 1.6 Preview?
Claude Sonnet 4.5 is available on Microsoft Foundry, Anthropic, Snowflake Cortex, GCP Vertex AI, and AWS Bedrock. Gemini Robotics-ER 1.6 Preview is available on the tracked providers still being sourced. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-11. Data sourced from public model cards and provider documentation.