Claude Sonnet 4.5 vs o3 Deep Research
Claude Sonnet 4.5 vs o3 Deep Research: Claude Sonnet 4.5 is cheaper for input-heavy usage ($3.00/M vs $10.00/M input tokens), while Claude Sonnet 4.5 is better for long-context tasks (200,000 tokens).
Direct answer: choose Claude Sonnet 4.5 for lower token spend and choose Claude Sonnet 4.5 when your workload needs longer context.
Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Sonnet 4.5
o3 Deep Research
Cost Differences
o3 Deep Research costs more than Claude Sonnet 4.5
Quick Recommendation
Winner for direct API pricing: Claude Sonnet 4.5. At the default workload, Claude Sonnet 4.5 saves about $58.50/month ($711.75/year) versus o3 Deep Research.
Feature Comparison
| Feature | Claude Sonnet 4.5 | o3 Deep Research |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $3.00/1M tokens | $10.00/1M tokens |
| Output Price | $15.00/1M tokens | $40.00/1M tokens |
| Context Window | 200,000 tokens | 200,000 tokens |
| Max Output | 64,000 tokens | 32,768 tokens |
| Category | balanced | reasoning |
| Capabilities | textvisioncode | textreasoningvisioncode |
| Release Date | 9/29/2025 | 6/26/2025 |
Claude Sonnet 4.5 vs o3 Deep Research: Which Should You Choose?
Choosing between Claude Sonnet 4.5 and o3 Deep Research 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 — 70% cheaper than o3 Deep Research.
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 o3 Deep Research is reasoning. This means they're optimized for different workloads. o3 Deep Research 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 $40.00 for o3 Deep Research. 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: Both models support vision (image understanding), so you can send images alongside text prompts with either option.
Best Use Cases
Choose Claude Sonnet 4.5 when:
- • Budget is a primary concern
- • You need longer outputs (up to 64,000 tokens)
- • You're already using Anthropic's API ecosystem
Choose o3 Deep Research when:
- • You need more capabilities (reasoning)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Claude Sonnet 4.5
- • Input pricing: $3.00/M tokens
- • Output pricing: $15.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 64,000 tokens
Watch out for
- • Trade-offs are minor in this matchup.
o3 Deep Research
- • Input pricing: $10.00/M tokens
- • Output pricing: $40.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 32,768 tokens
Watch out for
- • Higher input cost than Claude Sonnet 4.5
- • Higher output cost than Claude Sonnet 4.5
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Sonnet 4.5 (Anthropic)
o3 Deep Research (OpenAI)
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Which is cheaper, Claude Sonnet 4.5 or o3 Deep Research?▼
What is the context window difference between Claude Sonnet 4.5 and o3 Deep Research?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Anthropic and OpenAI API pricing beyond this model matchup?▼
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