Claude Sonnet 4.5 vs o1
Compare Anthropic and OpenAI AI models
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Sonnet 4.5
o1
Cost Differences
o1 costs more than Claude Sonnet 4.5
Feature Comparison
| Feature | Claude Sonnet 4.5 | o1 |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $3.00/1M tokens | $15.00/1M tokens |
| Output Price | $15.00/1M tokens | $60.00/1M tokens |
| Context Window | 200,000 tokens | 200,000 tokens |
| Max Output | 64,000 tokens | 65,536 tokens |
| Category | balanced | reasoning |
| Capabilities | textvisioncode | textreasoning |
| Release Date | 9/29/2025 | 9/12/2024 |
Claude Sonnet 4.5 vs o1: Which Should You Choose?
Choosing between Claude Sonnet 4.5 and o1 depends on your priorities: cost efficiency, context length, or raw capability. Claude Sonnet 4.5 is the more affordable option at $3.00/1M input tokens — 80% cheaper than o1.
These models come from different providers — Anthropic and OpenAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Anthropic, switching to OpenAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
These models target different tiers: Claude Sonnet 4.5 is a balanced model while o1 is reasoning. This means they're optimized for different workloads. o1 targets more demanding workloads, while Claude Sonnet 4.5 provides a cost-effective option for everyday tasks.
Output costs matter too. Claude Sonnet 4.5 charges $15.00/1M output tokens vs $60.00 for o1. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Claude Sonnet 4.5 has the edge here at $15.00/1M output tokens.
Multimodal capabilities: Claude Sonnet 4.5 supports vision (image inputs) while o1 is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose Claude Sonnet 4.5 when:
- • Budget is a primary concern
- • You need more capabilities (vision, code)
- • You're already using Anthropic's API ecosystem
Choose o1 when:
- • You need longer outputs (up to 65,536 tokens)
- • You're already using OpenAI's API ecosystem
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Sonnet 4.5 (Anthropic)
o1 (OpenAI)
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