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Claude 3 5 Sonnet vs GPT-5.1
This page is context-first: how much text each model can take in one request. Full specs adds capabilities and limits; the pricing matrix below is only about $/million tokens from hosts that list both models.
Context window · side by side
Bar length is relative to the larger of the two windows (100% = max of this pair). This is not pricing.
GPT-5.1 has about 1.4× the context window of the other in this pair.
GPT-5.1 has 36% more context capacity (272K vs 200K tokens). GPT-5.1 is 58% cheaper on input.
Quick verdicts
Short takeaways — validate with your own workloads.
Long document processing
Use GPT-5.1. Its 272K context fits entire documents without chunking (vs 200K).
RAG / high-volume retrieval
Use GPT-5.1. Input tokens are 58% cheaper — critical when sending large retrieved contexts.
Full specs
Context, output, capabilities, and dates. Green highlights the favorable value where we compute a winner.
| Spec | Claude 3 5 Sonnet | GPT-5.1 |
|---|---|---|
| Context window | 200,000 tokens (200K) | 272,000 tokens (272K) |
| Max output tokens | N/A | 128,000 tokens (128K) |
| Speed tier | Balanced | Balanced |
| Vision | No | Yes |
| Function calling | No | Yes |
| Extended thinking | No | Yes |
| Prompt caching | No | Yes |
| Batch API | Yes | No |
| Release date | N/A | Nov 2025 |
Pricing matrix
Dollar rates only: hosts that list both models, per 1M tokens. For how much text fits, use the context section above — not this table.
| Provider | Claude 3 5 Sonnet in | Claude 3 5 Sonnet out | GPT-5.1 in | GPT-5.1 out |
|---|---|---|---|---|
| Azure | — | — | $1.38/M | $11.00/M |
| Gmi | — | — | $1.25/M | $10.00/M |
| Google Vertex | $3.00/M | $15.00/M | — | — |
| Gradient | $3.00/M | $15.00/M | — | — |
| Openai | — | — | $1.25/M | $10.00/M |
| Openrouter | $3.00/M | $15.00/M | — | — |
| Replicate | $3.75/M | $18.75/M | — | — |
| Snowflake | — | — | — | — |
Frequently asked questions
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Example: a multi-turn chat session
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