Claude Haiku 4.5 vs Claude Mythos 5.1
Pricing verdict: Claude Haiku 4.5 vs Claude Mythos 5.1: Claude Haiku 4.5 is cheaper for input-heavy usage ($1.00/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 Claude Haiku 4.5 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 Haiku 4.5
Claude Mythos 5.1
Cost Differences
Claude Mythos 5.1 costs more than Claude Haiku 4.5
Quick Recommendation
Winner for direct API pricing: Claude Haiku 4.5. At the default workload, Claude Haiku 4.5 saves about $94.50/month ($1,149.75/year) versus Claude Mythos 5.1.
Feature Comparison
| Feature | Claude Haiku 4.5 | Claude Mythos 5.1 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Input Price | $1.00/1M tokens | $10.00/1M tokens |
| Output Price | $5.00/1M tokens | $50.00/1M tokens |
| Context Window | 200,000 tokens | 1,000,000 tokens |
| Max Output | 64,000 tokens | 128,000 tokens |
| Category | efficient | flagship |
| Capabilities | textvision | textvisionreasoningcode |
| Release Date | 10/15/2025 | 9/1/2026 |
Claude Haiku 4.5 vs Claude Mythos 5.1: Which Should You Choose?
Choosing between Claude Haiku 4.5 and Claude Mythos 5.1 depends on your priorities: cost efficiency, context length, or raw capability. Claude Haiku 4.5 is the more affordable option at $1.00/1M input tokens — 90% cheaper than Claude Mythos 5.1. Meanwhile, Claude Mythos 5.1 offers a significantly larger context window at 1,000,000 tokens vs 200,000 for Claude Haiku 4.5.
These models target different tiers: Claude Haiku 4.5 is a efficient model while Claude Mythos 5.1 is flagship. This means they're optimized for different workloads. Claude Mythos 5.1 targets more demanding workloads, while Claude Haiku 4.5 provides a cost-effective option for everyday tasks.
Output costs matter too. Claude Haiku 4.5 charges $5.00/1M output tokens vs $50.00 for Claude Mythos 5.1. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Claude Haiku 4.5 has the edge here at $5.00/1M 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 Haiku 4.5 when:
- • Budget is a primary concern
- • You're already using Anthropic's API ecosystem
- • You're running high-volume, latency-sensitive workloads
Choose Claude Mythos 5.1 when:
- • You need a larger context window (1,000,000 tokens)
- • You need more capabilities (reasoning, code)
- • You need longer outputs (up to 128,000 tokens)
- • You're already using Anthropic's API ecosystem
Pros and Caveats at a Glance
Claude Haiku 4.5
- • Input pricing: $1.00/M tokens
- • Output pricing: $5.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 64,000 tokens
Watch out for
- • Smaller context window than Claude Mythos 5.1
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 Claude Haiku 4.5
- • Higher output cost than Claude Haiku 4.5
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Haiku 4.5 (Anthropic)
Claude Mythos 5.1 (Anthropic)
Start using Claude Haiku 4.5 today
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Sign Up for Anthropic →Frequently Asked Questions
Which is cheaper, Claude Haiku 4.5 or Claude Mythos 5.1?▼
What is the context window difference between Claude Haiku 4.5 and Claude Mythos 5.1?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
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