Claude 3.5 Sonnet vs o3-pro
Claude 3.5 Sonnet vs o3-pro: Claude 3.5 Sonnet is cheaper for input-heavy usage ($3.00/M vs $20.00/M input tokens), while o3-pro is better for long-context tasks (1,000,000 tokens).
Direct answer: choose Claude 3.5 Sonnet for lower token spend and choose o3-pro 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 3.5 Sonnet
o3-pro
Cost Differences
o3-pro costs more than Claude 3.5 Sonnet
Quick Recommendation
Winner for direct API pricing: Claude 3.5 Sonnet. At the default workload, Claude 3.5 Sonnet saves about $148.50/month ($1,806.75/year) versus o3-pro.
Feature Comparison
| Feature | Claude 3.5 Sonnet | o3-pro |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $3.00/1M tokens | $20.00/1M tokens |
| Output Price | $15.00/1M tokens | $80.00/1M tokens |
| Context Window | 200,000 tokens | 1,000,000 tokens |
| Max Output | 8,192 tokens | 131,072 tokens |
| Category | balanced | reasoning |
| Capabilities | textvisioncode | textreasoningcode |
| Release Date | 10/22/2024 | 6/10/2025 |
Claude 3.5 Sonnet vs o3-pro: Which Should You Choose?
Choosing between Claude 3.5 Sonnet and o3-pro depends on your priorities: cost efficiency, context length, or raw capability. Claude 3.5 Sonnet is the more affordable option at $3.00/1M input tokens — 85% cheaper than o3-pro. Meanwhile, o3-pro offers a significantly larger context window at 1,000,000 tokens vs 200,000 for Claude 3.5 Sonnet.
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 3.5 Sonnet is a balanced model while o3-pro is reasoning. This means they're optimized for different workloads. o3-pro targets more demanding workloads, while Claude 3.5 Sonnet provides a cost-effective option for everyday tasks.
Output costs matter too. Claude 3.5 Sonnet charges $15.00/1M output tokens vs $80.00 for o3-pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Claude 3.5 Sonnet has the edge here at $15.00/1M output tokens.
Multimodal capabilities: Claude 3.5 Sonnet supports vision (image inputs) while o3-pro is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose Claude 3.5 Sonnet when:
- • Budget is a primary concern
- • You're already using Anthropic's API ecosystem
Choose o3-pro when:
- • You need a larger context window (1,000,000 tokens)
- • You need longer outputs (up to 131,072 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Claude 3.5 Sonnet
- • Input pricing: $3.00/M tokens
- • Output pricing: $15.00/M tokens
- • Context window: 200,000 tokens
- • Max output: 8,192 tokens
Watch out for
- • Smaller context window than o3-pro
o3-pro
- • Input pricing: $20.00/M tokens
- • Output pricing: $80.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Higher input cost than Claude 3.5 Sonnet
- • Higher output cost than Claude 3.5 Sonnet
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude 3.5 Sonnet (Anthropic)
o3-pro (OpenAI)
Start using Claude 3.5 Sonnet today
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Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Claude 3.5 Sonnet or o3-pro?▼
What is the context window difference between Claude 3.5 Sonnet and o3-pro?▼
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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