Claude Fable 5.2 vs Gemini 4 Carbon
Claude Fable 5.2 (2026) and Gemini 4 Carbon (2026) are frontier-tier reasoning models from Anthropic and Google DeepMind. Both ship a 1M-token context window. On AutomationBench, Gemini 4 Carbon leads by 2.5 pts. On pricing, Claude Fable 5.2 costs $8/1M input tokens; Gemini 4 Carbon ranges from $1 to $3.60/1M input tokens by tier. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.
Claude Fable 5.2 is safer overall; choose Gemini 4 Carbon when coding workflow support matters.
Decision scorecard
Local evidence first| Signal | Claude Fable 5.2 | Gemini 4 Carbon |
|---|---|---|
| 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 | Coding, RAG, and Agents |
| Context window | 1M | 1M |
| Cheapest output | $40/1M tokens | $5/1M tokens |
| Provider routes | 6 tracked | 4 tracked |
| Shared benchmarks | 7 shared | AutomationBench leader |
Decision tradeoffs
- Claude Fable 5.2 holds a shared-benchmark lead on FrontierCode 2.0, ahead by 9.1 points.
- Claude Fable 5.2 has broader tracked provider coverage for fallback and route flexibility.
- Local decision data tags Claude Fable 5.2 for Coding, RAG, and Agents.
- Gemini 4 Carbon holds a shared-benchmark lead on AutomationBench, ahead by 2.5 points.
- Gemini 4 Carbon has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Gemini 4 Carbon has the lower cheapest tracked output price at $5/1M tokens.
- Gemini 4 Carbon uniquely exposes Code execution in local model data.
- Local decision data tags Gemini 4 Carbon 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.
Claude Fable 5.2
$16,400
Cheapest tracked route/tier: Anthropic
Gemini 4 Carbon
$2,050
Cheapest tracked route/tier: Google AI Studio Flex
Estimated monthly gap: $14,350. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- Provider overlap exists on GCP Vertex AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
- Gemini 4 Carbon is $35/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Gemini 4 Carbon adds Code execution in local capability data.
- Provider overlap exists on GCP Vertex AI, OpenRouter, and Vercel AI Gateway; start route-level A/B tests there.
- Claude Fable 5.2 is $35/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Code execution before moving production traffic.
Specs
| Specification | ||
|---|---|---|
| Released | 2026-11-09 | 2026-10-28 |
| Context window | 1M | 1M |
| Parameters | — | — |
| Architecture | Decoder Only | - |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Weights | Not released | Not released |
| Code | Unknown | Unknown |
| Commercial use | Restricted | Restricted |
| Knowledge cutoff | 2026-06 | 2026-03 |
Pricing and availability
| Pricing attribute | Claude Fable 5.2 | Gemini 4 Carbon |
|---|---|---|
| Input price | $8/1M tokens |
|
| Output price | $40/1M tokens |
|
| Providers |
Capabilities
| Capability | Claude Fable 5.2 | Gemini 4 Carbon |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| JSON / Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | No | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Claude Fable 5.2 | Gemini 4 Carbon |
|---|---|---|
| AutomationBench | 51.4 | 53.9 |
| FrontierCode 2.0 | 49.1 | 40.0 |
| CursorBench | 53.2 | 58.6 |
| CursorBench | 54.8 | 58.6 |
| CursorBench | 56.3 | 58.6 |
| CursorBench | 56.9 | 58.6 |
| CursorBench | 60.0 | 58.6 |
Deep dive
On shared benchmark coverage, AutomationBench has Claude Fable 5.2 at 51.4 and Gemini 4 Carbon at 53.9, with Gemini 4 Carbon ahead by 2.5 points; FrontierCode 2.0 has Claude Fable 5.2 at 49.1 and Gemini 4 Carbon at 40, with Claude Fable 5.2 ahead by 9.1 points; CursorBench has Claude Fable 5.2 at 53.2 and Gemini 4 Carbon at 58.6, with Gemini 4 Carbon ahead by 5.4 points. The largest visible gap is 9.1 points on FrontierCode 2.0, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.
The capability footprint differs most on JSON / Tool use: Claude Fable 5.2 and code execution: Gemini 4 Carbon. Both models share vision, multimodal input, reasoning mode, and JSON / Tool use, 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 Fable 5.2 lists $8/1M input and $40/1M output tokens on the cheapest listed provider, while Gemini 4 Carbon lists tiered pricing: Flex is $1/1M input and $5/1M output; Standard is $2/1M input and $10/1M output; Priority is $3.60/1M input and $18/1M output. A 70/30 input-output blend puts Gemini 4 Carbon lower by about $15.40 per million blended tokens. For tiered pricing, this cheapest-route view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 6 providers versus 4, so concentration risk also matters.
Choose Claude Fable 5.2 when vision-heavy evaluation and broader provider choice are central to the workload. Choose Gemini 4 Carbon when coding workflow support, larger context windows, and lower cheapest-tier input-token cost are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.
FAQ
Which has a larger context window, Claude Fable 5.2 or Gemini 4 Carbon?
Gemini 4 Carbon supports 1M tokens, while Claude Fable 5.2 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 Fable 5.2 or Gemini 4 Carbon?
Claude Fable 5.2 lists $8/1M input and $40/1M output tokens on the cheapest listed provider. Gemini 4 Carbon lists tiered pricing: Flex is $1/1M input and $5/1M output; Standard is $2/1M input and $10/1M output; Priority is $3.60/1M input and $18/1M output. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.
Is Claude Fable 5.2 or Gemini 4 Carbon open source?
Claude Fable 5.2 is listed under Proprietary. Gemini 4 Carbon 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 Fable 5.2 or Gemini 4 Carbon?
Both Claude Fable 5.2 and Gemini 4 Carbon 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 Fable 5.2 or Gemini 4 Carbon?
Both Claude Fable 5.2 and Gemini 4 Carbon 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 Fable 5.2 and Gemini 4 Carbon?
Claude Fable 5.2 is available on Anthropic, AWS Bedrock, GCP Vertex AI, OpenRouter, and Vercel AI Gateway. Gemini 4 Carbon is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-11-10. Data sourced from public model cards and provider documentation.