Model comparison - Same provider, successor
Claude Sonnet 5 vs Claude Sonnet 5.5
Claude Sonnet 5 and Claude Sonnet 5.5 are both Anthropic models. Both list the same first-party API price: $2 per 1M input tokens and $10 per 1M output tokens. Claude Sonnet 5 and Claude Sonnet 5.5 both have a 1,000,000-token context window, and both return up to 128,000 output tokens per response. Claude Sonnet 5 was released on June 30, 2026 and Claude Sonnet 5.5 on September 28, 2026. Both are closed-weights models, available only through an API.
Last verified from each provider's pricing page. All sources
Side-by-side specs
| Spec | Claude Sonnet 5 | Claude Sonnet 5.5 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Input / 1M tokens | $2 | $2 |
| Output / 1M tokens | $10 | $10 |
| Cache read / 1M | $0.20 | $0.10 |
| Cache write / 1M | $2.50 | $2.50 |
| Batch input / 1M | $1 | $1 |
| Batch output / 1M | $5 | $5 |
| Context window | 1,000,000 | 1,000,000 |
| Max output | 128,000 | 128,000 |
| Release date | ||
| Weights | Closed | Closed |
| API model id | claude-sonnet-5 | claude-sonnet-5-5 |
| AI Gateway id | anthropic/claude-sonnet-5 | anthropic/claude-sonnet-5.5 |
| Last verified |
Prices in USD per 1M tokens at each provider's standard first-party rate. A dash means the provider does not bill that item separately or no primary page states it.
What each costs in practice
The same three workloads every model page uses, worked from each model's standard list rates. Swap in your own token counts with the math on each model's page.
| Workload | Claude Sonnet 5 | Claude Sonnet 5.5 |
|---|---|---|
| One agent session1M input tokens and 100K output tokens, no caching. | $3.00 | $3.00 |
| A chat app10,000 requests a day at 2K input and 500 output tokens each. | $90.00$2,700.00 per 30-day month | $90.00$2,700.00 per 30-day month |
| The same session at a 90% cache hit90% of the input is read from the prompt cache. The one-time cache write premium is not included. | $1.38 | $1.29 |
Show the math
Claude Sonnet 5
- One agent sessionInput: 1M x $2 = $2.00Output: 0.1M x $10 = $1.00
- A chat appInput: 20M x $2 = $40.00Output: 5M x $10 = $50.00
- The same session at a 90% cache hitCached input: 0.9M x $0.20 = $0.18Uncached input: 0.1M x $2 = $0.20Output: 0.1M x $10 = $1.00
Claude Sonnet 5.5
- One agent sessionInput: 1M x $2 = $2.00Output: 0.1M x $10 = $1.00
- A chat appInput: 20M x $2 = $40.00Output: 5M x $10 = $50.00
- The same session at a 90% cache hitCached input: 0.9M x $0.10 = $0.09Uncached input: 0.1M x $2 = $0.20Output: 0.1M x $10 = $1.00
Benchmarks under the same setting
Only boards that list both models under the same run setting appear here, one row per board and setting, with each score exactly as the board shows it. Scores on different boards use different scales and are never combined.
| Board and setting | Claude Sonnet 5 | Claude Sonnet 5.5 |
|---|---|---|
| Terminal-Bench 4.0agent: Claude Code; effort: maxOfficial leaderboard - tbench.ai | 12.4% ± 3.1% | 61.8% ± 2.9% |
Model pages
FAQ
How do Claude Sonnet 5 and Claude Sonnet 5.5 compare on price?
Both list the same first-party API price: $2 per 1M input tokens and $10 per 1M output tokens. For one agent session of 1M input and 100K output tokens with no caching, that is $3.00 on Claude Sonnet 5 and $3.00 on Claude Sonnet 5.5. Prices are each provider's first-party list rates, verified October 17, 2026 and October 17, 2026.
What are the context windows of Claude Sonnet 5 and Claude Sonnet 5.5?
Claude Sonnet 5 and Claude Sonnet 5.5 both have a 1,000,000-token context window, and both return up to 128,000 output tokens per response.
Are Claude Sonnet 5 and Claude Sonnet 5.5 open weights?
Claude Sonnet 5 is closed-weights and is called through Anthropic's API as claude-sonnet-5. Claude Sonnet 5.5 is closed-weights and is called through Anthropic's API as claude-sonnet-5-5.
More comparisons
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- Claude Sonnet 4.6 vs Claude Sonnet 5Same provider, successor
- Claude Sonnet 5.5 vs GPT-6.1 SolSimilar price, same tier
- Claude Sonnet 5.5 vs Grok 4.7Similar price, same tier
- Claude Sonnet 5.5 vs GLM-5.3Open weights vs closed
- Claude Sonnet 5.5 vs Qwen3.8-2.4T-A95BSimilar price, same tier
- Claude Sonnet 5.5 vs Qwen3.8-MaxSimilar price, same tier
- Claude Sonnet 5.5 vs DeepSeek V4 ProOpen weights vs closed
Sources
Claude Sonnet 5 verified from platform.claude.com; Claude Sonnet 5.5 verified from platform.claude.com. This page is as current as the older of the two: .
- https://platform.claude.com/docs/en/about-claude/pricing
- https://platform.claude.com/docs/en/models/sonnet-5/overview
- https://platform.claude.com/docs/en/about-claude/models/overview
- https://platform.claude.com/docs/en/release-notes/overview
- https://platform.claude.com/docs/en/about-claude/model-deprecations
- https://platform.claude.com/docs/en/models/sonnet-5-5/overview
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