Side-by-side technical and economic comparison between DeepSeek's DeepSeek-V3 (Legacy API Alias) and DeepSeek's DeepSeek-V4.1-Reasoner.
• DeepSeek-V3 (Legacy API Alias): Classified as a Legacy Reference model (Legacy Reference (API Aliased)).
| Metric | DeepSeek-V3 (Legacy API Alias) | DeepSeek-V4.1-Reasoner | Advantage |
|---|---|---|---|
| Provider Organization | DeepSeek | DeepSeek | — |
| Standard Input / 1M | $0.14 | $0.50 | DeepSeek-V3 (Legacy API Alias) (72% lower) |
| Cached Input / 1M | $0.014 | $0.01 | DeepSeek-V4.1-Reasoner lower |
| Output / 1M | $0.28 | $2.50 | DeepSeek-V3 (Legacy API Alias) lower |
| Context Window | 128k | 256k | DeepSeek-V4.1-Reasoner (256k) |
| Max Generation Tokens | 8.2k | 384k | DeepSeek-V4.1-Reasoner |
| Tokenizer Family | DeepSeek Byte-level BPE (~128k vocabulary) | DeepSeek Byte-Level BPE (102k vocabulary) | — |
Opt for DeepSeek-V3 (Legacy API Alias) when your engineering requirements prioritize DeepSeek's ecosystem, specific tokenizer efficiencies (Exact DeepSeek Tokenizer (±2%)), or when your expected prompt-to-completion ratios favor its $0.14/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.