Model comparison - Open weights vs closed
Claude Sonnet 5.5 vs DeepSeek V4 Pro
Claude Sonnet 5.5 is from Anthropic and DeepSeek V4 Pro is from DeepSeek. On list price, Claude Sonnet 5.5 charges 1.5x DeepSeek V4 Pro's input price ($2 vs $1.32 per 1M tokens), and Claude Sonnet 5.5 charges 2.5x DeepSeek V4 Pro's output price ($10 vs $3.96 per 1M tokens). Claude Sonnet 5.5 and DeepSeek V4 Pro both have a 1,000,000-token context window; max output is 128,000 and 393,216 tokens per response. Claude Sonnet 5.5 was released on September 28, 2026 and DeepSeek V4 Pro on April 24, 2026. DeepSeek V4 Pro publishes open weights (MIT); Claude Sonnet 5.5 is closed-weights.
Last verified from each provider's pricing page. All sources
Side-by-side specs
| Spec | Claude Sonnet 5.5 | DeepSeek V4 Pro |
|---|---|---|
| Provider | Anthropic | DeepSeek |
| Input / 1M tokens | $2 | $1.32 |
| Output / 1M tokens | $10 | $3.96 |
| Cache read / 1M | $0.10 | $0.044 |
| Cache write / 1M | $2.50 | - |
| Batch input / 1M | $1 | - |
| Batch output / 1M | $5 | - |
| Context window | 1,000,000 | 1,000,000 |
| Max output | 128,000 | 393,216 |
| Release date | ||
| Weights | Closed | Open |
| License | - | MIT |
| API model id | claude-sonnet-5-5 | deepseek-v4-pro |
| AI Gateway id | anthropic/claude-sonnet-5.5 | deepseek/deepseek-v4-pro |
| 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 5.5 | DeepSeek V4 Pro |
|---|---|---|
| One agent session1M input tokens and 100K output tokens, no caching. | $3.00 | $1.72 |
| A chat app10,000 requests a day at 2K input and 500 output tokens each. | $90.00$2,700.00 per 30-day month | $46.20$1,386.00 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. | $1.29 | $0.5676 |
Show the math
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
DeepSeek V4 Pro
- One agent sessionInput: 1M x $1.32 = $1.32Output: 0.1M x $3.96 = $0.396
- A chat appInput: 20M x $1.32 = $26.40Output: 5M x $3.96 = $19.80
- The same session at a 90% cache hitCached input: 0.9M x $0.044 = $0.0396Uncached input: 0.1M x $1.32 = $0.132Output: 0.1M x $3.96 = $0.396
Benchmarks under the same setting
No board in the benchmark directory lists both Claude Sonnet 5.5 and DeepSeek V4 Pro under the same setting, so there is no like-for-like score to show here.
Set them up in your tools
Step-by-step guides whose official docs list Claude Sonnet 5.5 or DeepSeek V4 Pro by model id.
- Use DeepSeek in AiderLists DeepSeek V4 Pro
- Use DeepSeek in Claude CodeLists DeepSeek V4 Pro
- Use DeepSeek in ClineLists DeepSeek V4 Pro
- Use DeepSeek in Codex CLILists DeepSeek V4 Pro
- Use DeepSeek in ContinueLists DeepSeek V4 Pro
- Use DeepSeek in GitHub CopilotLists DeepSeek V4 Pro
- Use DeepSeek in GooseLists DeepSeek V4 Pro
- Use DeepSeek in Kilo CodeLists DeepSeek V4 Pro
- Use DeepSeek in OpenCodeLists DeepSeek V4 Pro
- Use DeepSeek in Roo CodeLists DeepSeek V4 Pro
- Use DeepSeek in ZedLists DeepSeek V4 Pro
Model pages
FAQ
How do Claude Sonnet 5.5 and DeepSeek V4 Pro compare on price?
On list price, Claude Sonnet 5.5 charges 1.5x DeepSeek V4 Pro's input price ($2 vs $1.32 per 1M tokens), and Claude Sonnet 5.5 charges 2.5x DeepSeek V4 Pro's output price ($10 vs $3.96 per 1M tokens). For one agent session of 1M input and 100K output tokens with no caching, that is $3.00 on Claude Sonnet 5.5 and $1.72 on DeepSeek V4 Pro. 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 5.5 and DeepSeek V4 Pro?
Claude Sonnet 5.5 and DeepSeek V4 Pro both have a 1,000,000-token context window; max output is 128,000 and 393,216 tokens per response.
Are Claude Sonnet 5.5 and DeepSeek V4 Pro open weights?
Claude Sonnet 5.5 is closed-weights and is called through Anthropic's API as claude-sonnet-5-5. DeepSeek V4 Pro's weights are published at huggingface.co under the MIT.
More comparisons
- Claude Sonnet 5.5 vs Gemini 4 ArgonSimilar price, same tier
- DeepSeek V4 Pro vs Gemini 4 ArgonOpen weights vs closed
- Claude Sonnet 5.5 vs GPT-6.1 SolSimilar price, same tier
- DeepSeek V4 Pro vs Mistral Large 4Similar price, same tier
- Claude Sonnet 5.5 vs Grok 4.7Similar price, same tier
- DeepSeek V4 Pro vs GPT-6.1 SolOpen weights vs closed
- Claude Sonnet 5.5 vs GLM-5.3Open weights vs closed
- Claude Sonnet 5.5 vs Qwen3.8-2.4T-A95BSimilar price, same tier
Sources
Claude Sonnet 5.5 verified from platform.claude.com; DeepSeek V4 Pro verified from api-docs.deepseek.com. This page is as current as the older of the two: .
- https://platform.claude.com/docs/en/about-claude/pricing
- https://api-docs.deepseek.com/quick_start/pricing
- https://platform.claude.com/docs/en/models/sonnet-5-5/overview
- https://platform.claude.com/docs/en/about-claude/models/overview
- https://platform.claude.com/docs/en/release-notes/overview
- https://api-docs.deepseek.com/updates
- https://api-docs.deepseek.com/news/news260424
- https://api-docs.deepseek.com/news/news260813
- https://api-docs.deepseek.com/news/news260910
- https://huggingface.co/deepseek-ai/DeepSeek-V4-Pro
- https://vercel.com/ai-gateway/models/deepseek-v4-pro
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