Claude Sonnet 5.5
- Family
- Claude 5.5
- Released
- 2026-09-28
- Context
- 1M
- Max output
- 128K
- Architecture
- Decoder Only
- Knowledge cutoff
- 2026-06
- Specialization
- general
- Openness
- Proprietary
- License
- ProprietaryCommercial use: conditional
- Weights
- Not released
- Code
- Unknown
- Training
- Pretrained
Cheapest of 5 routes · Anthropic · cache read $0.100
About
Anthropic's Claude Sonnet 5.5, second model in the Claude 5.5 family, released September 28, 2026. First-party positioning: faster, lower-cost complement to Claude Opus 5.5; strongest at well-scoped everyday tasks, bug fixes, and polished documents/slides/spreadsheets; clear upgrade over Claude Sonnet 5 (30%+ faster output; up to 30% less cost per task via fewer tokens — list price unchanged vs Sonnet 5). Claude API id claude-sonnet-5-5. List price $2 per 1M input and $10 per 1M output; cache reads $0.10 / MTok; 5m cache writes $2.50; 1h cache writes $4; Batch API 50% off ($1/$5).
Providers(5)
Compare all 5Compare API pricing across 5 tracked provider routes for input and output tokens, batch, and cached reads when available.
| Provider | Input / 1M | Output / 1M | Batch in / out | Cache | Route |
|---|---|---|---|---|---|
| Anthropic | $2.00 | $10.00 | $1.00 / $5.00 | read $0.100 / 5m $2.50 / 1h $4.00 | Serverless |
| AWS Bedrock | $2.00 | $10.00 | - | read $0.100 / 5m $2.50 / 1h $4.00 | Serverless |
| GCP Vertex AI | $2.00 | $10.00 | - | read $0.100 / 5m $2.50 / 1h $4.00 | Serverless |
| Microsoft Foundry | $2.00 | $10.00 | - | read $0.100 / 5m $2.50 / 1h $4.00 | Serverless |
| OpenRouter | $2.00 | $10.00 | - | read $0.100 | Serverless |
Available via routers & gateways(16)
LiteLLM
GatewayOpen-source Python SDK and proxy server that unifies 100+ LLM APIs behind a single OpenAI-compatible interface, with load balancing, cost tracking, and configurable failover.
OpenRouter
HybridUnified hybrid gateway to 400+ models from 60+ providers via a single OpenAI-compatible API, with optional auto-routing that selects the best model per prompt.
Portkey
GatewayProduction AI gateway routing to 1,600+ LLMs with failover, load balancing, semantic caching, and guardrails; Apache 2.0 core is fully self-hostable with the complete feature set.
AIRouter
RouterCommercial LLM router that analyzes incoming requests and routes to the optimal model for cost/quality/latency via a drop-in OpenAI-compatible API, with a privacy-preserving embedding mode that avoids sending prompt content.
Amazon Bedrock Intelligent Prompt Routing
RouterAWS Bedrock's native intelligent prompt router that routes prompts between Anthropic Claude model tiers (Haiku/Sonnet) based on predicted task complexity, with no extra per-routing charge.
Azure AI Foundry Model Router
RouterMicrosoft Azure AI Foundry's native model router that uses a trained ML model to route each prompt in real time to the optimal Azure-hosted model, with Balanced/Cost/Quality mode selection and automatic failover.
Capabilities
Benchmark peer barsfor Coding
No task-mapped benchmark peers are available for this model yet.
Benchmark scores(4)
| Benchmark | Score | Version | Evaluation | Source |
|---|---|---|---|---|
| CursorBench | 55.5 | CursorBench 4.0Observed 2026-10-05 | Configuration: claude-sonnet-5-5 (Max) Harness: CursorBench 4.0 productized Cursor-agent workflow Evaluator: Cursor Confidence: confirmed Cost/task: $9.67 Tokens/task: 271,920 Steps/task: 170 Notes: Cursor vendor-reported CursorBench 4.0 configuration result; verified on https://cursor.com/cursorbench chart label 'Sonnet 5.5 Max' (retrieved 2026-10-05). Not independently reproducible. Highest-scoring published configuration selected; timestamp is retrieval date (page carries no per-row date). Cost/tokens/steps from cursor.com/cursorbench table row (same retrieval). | Source |
| FrontierCode 1.1 Main | 52.1 | FrontierCode 1.1 MainObserved 2026-10-05 | Configuration: claude-sonnet-5-5 (Extra High) Harness: claude-code Evaluator: Cognition Confidence: confirmed Notes: Cognition FrontierCode 1.1 Main (100 tasks) mean@5 composite ('new_score'), verified in https://cognition.com/data/frontiercode-leaderboard/data.json (the data file behind https://cognition.com/frontiercode), retrieved 2026-10-05. Agent harness: claude-code. Highest-scoring published effort selected; timestamp is retrieval date. | Source |
| FrontierMath Tier 4 | 80.5 | FrontierMath Tier 4 v2 (private)Observed 2026-09-29 | Configuration: claude-sonnet-5-5 (Max) Harness: Epoch AI FrontierMath Tier 4 v2 private set Evaluator: Epoch AI Confidence: confirmed Notes: Epoch AI-run evaluation (evaluator of record), from Epoch AI Benchmarking Hub data download https://epoch.ai/data/benchmark_data.zip (file frontiermath_tier_4_v2.csv, row 'claude-sonnet-5-5_max', run started 2026-09-29). Epoch data is CC BY 4.0: credit 'Epoch AI, Capabilities & benchmarking, https://epoch.ai/benchmarks'. Highest-scoring Epoch configuration for this model selected; other configurations exist in the same file. Discovered via Benchmark Heaven (lead only). | Source |
| Google-Proof Q&A | 95.6 | diamondObserved 2026-09-29 | Configuration: claude-sonnet-5-5 (Max) Harness: Epoch AI Inspect harness (GPQA Diamond, 198 Q) Evaluator: Epoch AI Confidence: confirmed Notes: Epoch AI-run evaluation (evaluator of record), from Epoch AI Benchmarking Hub data download https://epoch.ai/data/benchmark_data.zip (file gpqa_diamond.csv, row 'claude-sonnet-5-5_max', run started 2026-09-29). Epoch data is CC BY 4.0: credit 'Epoch AI, Capabilities & benchmarking, https://epoch.ai/benchmarks'. Highest-scoring Epoch configuration for this model selected; other configurations exist in the same file. Discovered via Benchmark Heaven (lead only). | Source |
Migration checks
No linked migration route is available for this model yet.
API versions
claude-sonnet-5-5Claude Sonnet 5.5Sonnet 5.5Cheapest of 5 routes · Anthropic · cache read $0.100