Prior Sonnet generation; see Anthropic deprecations for migration timelines.
Model details →Claude Sonnet 4.5 vs DeepSeek V4 Flash
Claude Sonnet 4.5 and DeepSeek V4 Flash are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
DeepSeek V4 Flash — 1M context, thinking and non-thinking modes; see DeepSeek pricing/docs for current capabilities.
Model details →Side-by-side comparison
| Capability | Claude Sonnet 4.5 | DeepSeek V4 Flash | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 200K | 1M | 🏆 DeepSeek V4 Flash |
| Input price (per 1M) Cost per million input tokens billed by the provider. | Custom | Custom | — |
| Output price (per 1M) Cost per million output tokens billed by the provider. | Custom | Custom | — |
| Tool / function calling First-class support for emitting structured tool calls. | — | — | Tie |
| Vision input Accepts image inputs alongside text. | Yes | — | 🏆 Claude Sonnet 4.5 |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | — | — | Tie |
Frequently asked questions
Is Claude Sonnet 4.5 better than DeepSeek V4 Flash?
Claude Sonnet 4.5 and DeepSeek V4 Flash are evenly matched on 6 axes — pick the one whose provider, latency, or licensing fits your stack.
What's the price difference between Claude Sonnet 4.5 and DeepSeek V4 Flash?
Input: Custom vs Custom per 1M tokens. Output: Custom vs Custom per 1M tokens.
What context windows do Claude Sonnet 4.5 and DeepSeek V4 Flash support?
Claude Sonnet 4.5 supports up to 200K tokens. DeepSeek V4 Flash supports up to 1M tokens.
Do both Claude Sonnet 4.5 and DeepSeek V4 Flash support tool calling?
Claude Sonnet 4.5: not advertised. DeepSeek V4 Flash: not advertised.