Model comparison
Claude Opus 4.8 vs Grok 3
Anthropic
Claude Opus 4.8
Anthropic's heavyweight for hard reasoning and agentic work.
xAI
Grok 3
xAI's third-generation model - superseded by Grok 4.
Specs
| Metric | Claude Opus 4.8 | Grok 3 |
|---|---|---|
| Context window | 1M tokens↑ | 131K tokens |
| Input $/1M tokens | $5.00 | $3.00↑ |
| Output $/1M tokens | $25.00 | $15.00↑ |
| Modalities | Text · Image | Text |
| Open weights | No | No |
| Released | May 2026 | - |
Capability differences
| Capability | Claude Opus 4.8 | Grok 3 |
|---|---|---|
| Prompt caching | Yes | No |
Key differences
- -Claude Opus 4.8 offers 1M context; Grok 3 offers 131K.
- -Input pricing: Claude Opus 4.8 at $5.00/1M vs Grok 3 at $3.00/1M.