Side-by-side technical and economic comparison between Anthropic's Claude Sonnet 5 and xAI's Grok 2.
• Grok 2: Classified as a Legacy Reference model (Generally Available).
| Metric | Claude Sonnet 5 | Grok 2 | Advantage |
|---|---|---|---|
| Provider Organization | Anthropic | xAI | — |
| Standard Input / 1M | $2.00 | $2.00 | Identical |
| Cached Input / 1M | $0.20 | None | Claude Sonnet 5 lower |
| Output / 1M | $10.00 | $10.00 | Identical |
| Context Window | 1M | 128k | Claude Sonnet 5 (1M) |
| Max Generation Tokens | 16.4k | 8.2k | Claude Sonnet 5 |
| Tokenizer Family | Anthropic Claude BPE (~65k vocabulary) | xAI Byte-level BPE (~131k vocabulary) | — |
Opt for Claude Sonnet 5 when your engineering requirements prioritize Anthropic's ecosystem, specific tokenizer efficiencies (Calibrated Claude Tokenizer (±3%)), or when your expected prompt-to-completion ratios favor its $2/M input rate.
Opt for Grok 2 when looking for xAI's tooling integration, specific context window depth (128k tokens), or when output generation volume favors its $10/M rate.