Claude Opus 4.8 (Fast) vs Gemini 3.1 Pro Preview
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Claude Opus 4.8 (Fast) and Gemini 3.1 Pro Preview.
Claude Opus 4.8 (Fast)
Fast-mode variant of [Opus 4.8](/anthropic/claude-opus-4.8) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 4.8. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-mode
Gemini 3.1 Pro Preview
Gemini 3.1 Pro Preview is Google’s frontier reasoning model, delivering enhanced software engineering performance, improved agentic reliability, and more efficient token usage across complex workflows. Building on the multimodal foundation...
Technical Specifications
| Specification | Claude Opus 4.8 (Fast) | Gemini 3.1 Pro Preview |
|---|---|---|
| Provider | Anthropic | |
| Context Window | 1,000,000 tokens | 1,048,576 tokens |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | beta | beta |
| API Available | Yes | Yes |
| Released Date | 2026-05-27 | 2026-02-19 |
API Pricing Comparison
Input Price per Million Tokens
Claude Opus 4.8 (Fast)
$10.00
Gemini 3.1 Pro Preview
$2.00
Output Price per Million Tokens
Claude Opus 4.8 (Fast)
$50.00
Gemini 3.1 Pro Preview
$12.00
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Claude Opus 4.8 (Fast) Quirks & Gotchas
No developer gotchas reported.
Gemini 3.1 Pro Preview Quirks & Gotchas
No developer gotchas reported.