Side-by-side technical and economic comparison between DeepSeek's DeepSeek-V4.1-Flash and DeepSeek's DeepSeek-V4.1-Reasoner.
| Metric | DeepSeek-V4.1-Flash | DeepSeek-V4.1-Reasoner | Advantage |
|---|---|---|---|
| Provider Organization | DeepSeek | DeepSeek | — |
| Standard Input / 1M | $0.30 | $0.50 | DeepSeek-V4.1-Flash (40% lower) |
| Cached Input / 1M | $0.006 | $0.01 | DeepSeek-V4.1-Flash lower |
| Output / 1M | $1.20 | $2.50 | DeepSeek-V4.1-Flash lower |
| Context Window | 1.05M | 256k | DeepSeek-V4.1-Flash (1.05M) |
| Max Generation Tokens | 384k | 384k | DeepSeek-V4.1-Flash |
| Tokenizer Family | DeepSeek Byte-Level BPE (100k vocabulary) | DeepSeek Byte-Level BPE (102k vocabulary) | — |
Opt for DeepSeek-V4.1-Flash when your engineering requirements prioritize DeepSeek's ecosystem, specific tokenizer efficiencies (Calibrated DeepSeek Tokenizer (±3%)), or when your expected prompt-to-completion ratios favor its $0.3/M input rate.
Opt for DeepSeek-V4.1-Reasoner when looking for DeepSeek's tooling integration, specific context window depth (256k tokens), or when output generation volume favors its $2.5/M rate.