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Claude 3.5 Sonnet vs o3-pro

Compare Anthropic and OpenAI AI models

Anthropic
Claude 3.5 Sonnet
vs
OpenAI
o3-pro

Cost Comparison (1000 input + 500 output tokens, 100 requests/day)

Claude 3.5 Sonnet

Per Request:$0.0105
Daily:$1.05
Monthly:$31.50
Yearly:$383.25

o3-pro

Per Request:$0.06
Daily:$6.00
Monthly:$180.00
Yearly:$2,190.00

Cost Differences

+$0.0495
Per Request
+$4.95
Daily
+$148.50
Monthly
+$1,806.75
Yearly

o3-pro costs more than Claude 3.5 Sonnet

Feature Comparison

FeatureClaude 3.5 Sonneto3-pro
ProviderAnthropicOpenAI
Input Price$3.00/1M tokens$20.00/1M tokens
Output Price$15.00/1M tokens$80.00/1M tokens
Context Window200,000 tokens1,000,000 tokens
Max Output8,192 tokens131,072 tokens
Categorybalancedreasoning
Capabilities
textvisioncode
textreasoningcode
Release Date10/22/20246/10/2025

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 tokens85% 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

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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Start using o3-pro today

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Frequently Asked Questions

Which is cheaper, Claude 3.5 Sonnet or o3-pro?
Claude 3.5 Sonnet is cheaper for input tokens at $3.00 per million tokens vs $20.00 for o3-pro — that's 85% savings on input costs.
What is the context window difference between Claude 3.5 Sonnet and o3-pro?
Claude 3.5 Sonnet supports 200,000 tokens while o3-pro supports 1,000,000 tokens — a difference of 800,000 tokens in favor of o3-pro.
Which model is better for AI Chatbot?
Both models support text. For ai chatbot, Claude 3.5 Sonnet is the lower-cost option, while o3-pro offers a larger context window (1,000,000 vs 200,000 tokens). Choose Claude 3.5 Sonnet for budget sensitivity or o3-pro for longer context tasks.
Which model has better overall pricing for heavy usage?
At 100 requests/day with 1,000 input and 500 output tokens each, Claude 3.5 Sonnet costs about $31.50/month and o3-pro costs about $180.00/month. Overall, Claude 3.5 Sonnet has lower combined input + output rates ($3.00 in, $15.00 out) vs o3-pro.

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