Claude Mythos 5.1 vs Gemini 3.1 Pro
Pricing verdict: Claude Mythos 5.1 vs Gemini 3.1 Pro: Gemini 3.1 Pro is cheaper for input-heavy usage ($2.00/M vs $10.00/M input tokens), while Claude Mythos 5.1 is better for long-context tasks (1,000,000 tokens).
Direct answer: choose Gemini 3.1 Pro for lower token spend and choose Claude Mythos 5.1 when your workload needs longer context.
Compare API pricing, input and output token costs, context windows, and monthly estimates on one page so you can pick the right model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Mythos 5.1
Gemini 3.1 Pro
Cost Differences
Gemini 3.1 Pro costs less than Claude Mythos 5.1
Quick Recommendation
Winner for direct API pricing: Gemini 3.1 Pro. At the default workload, Gemini 3.1 Pro saves about $81.00/month ($985.50/year) versus Claude Mythos 5.1.
Feature Comparison
| Feature | Claude Mythos 5.1 | Gemini 3.1 Pro |
|---|---|---|
| Provider | Anthropic | |
| Input Price | $10.00/1M tokens | $2.00/1M tokens |
| Output Price | $50.00/1M tokens | $12.00/1M tokens |
| Context Window | 1,000,000 tokens | 1,000,000 tokens |
| Max Output | 128,000 tokens | 65,536 tokens |
| Category | flagship | flagship |
| Capabilities | textvisionreasoningcode | textvisionaudiovideocodereasoning |
| Release Date | 9/1/2026 | 2/19/2026 |
Claude Mythos 5.1 vs Gemini 3.1 Pro: Which Should You Choose?
Choosing between Claude Mythos 5.1 and Gemini 3.1 Pro depends on your priorities: cost efficiency, context length, or raw capability. Gemini 3.1 Pro is the more affordable option at $2.00/1M input tokens — 80% cheaper than Claude Mythos 5.1.
These models come from different providers — Anthropic and Google — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Anthropic, switching to Googleinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
Both models are in the flagship category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: Gemini 3.1 Pro would save you roughly $8,100.00/month compared to Claude Mythos 5.1. For startups and indie developers, that difference can be significant.
Output costs matter too. Claude Mythos 5.1 charges $50.00/1M output tokens vs $12.00 for Gemini 3.1 Pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Gemini 3.1 Pro has the edge here at $12.00/1M output tokens.
Multimodal capabilities: Both models support vision (image understanding), so you can send images alongside text prompts with either option.
Best Use Cases
Choose Claude Mythos 5.1 when:
- • You need longer outputs (up to 128,000 tokens)
- • You're already using Anthropic's API ecosystem
Choose Gemini 3.1 Pro when:
- • Budget is a primary concern
- • You need more capabilities (audio, video)
- • You're already using Google's API ecosystem
Pros and Caveats at a Glance
Claude Mythos 5.1
- • Input pricing: $10.00/M tokens
- • Output pricing: $50.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher input cost than Gemini 3.1 Pro
- • Higher output cost than Gemini 3.1 Pro
Gemini 3.1 Pro
- • Input pricing: $2.00/M tokens
- • Output pricing: $12.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 65,536 tokens
Watch out for
- • Trade-offs are minor in this matchup.
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Mythos 5.1 (Anthropic)
Gemini 3.1 Pro (Google)
Start using Claude Mythos 5.1 today
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Sign Up for Google →Frequently Asked Questions
Which is cheaper, Claude Mythos 5.1 or Gemini 3.1 Pro?▼
What is the context window difference between Claude Mythos 5.1 and Gemini 3.1 Pro?▼
Which model is better for AI Agent / Agentic Workflows?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Anthropic and Google API pricing beyond this model matchup?▼
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