Claude Sonnet 4 vs GPT-5.5 Pro
Claude Sonnet 4 vs GPT-5.5 Pro: Claude Sonnet 4 is cheaper for input-heavy usage ($3.00/M vs $30.00/M input tokens), while GPT-5.5 Pro is better for long-context tasks (1,050,000 tokens).
Direct answer: choose Claude Sonnet 4 for lower token spend and choose GPT-5.5 Pro when your workload needs longer context.
Common pricing searches covered on this page: Claude Sonnet 4 vs GPT-5.5 Pro • Claude Sonnet 4 vs GPT-5.5 Pro pricing • Claude Sonnet 4 vs GPT-5.5 Pro API pricing and sonnet 4 vs 5 5 pro pricing.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Sonnet 4
GPT-5.5 Pro
Cost Differences
GPT-5.5 Pro costs more than Claude Sonnet 4
Quick Recommendation
Winner for direct API pricing: Claude Sonnet 4. At the default workload, Claude Sonnet 4 saves about $328.50/month ($3,996.75/year) versus GPT-5.5 Pro.
Feature Comparison
| Feature | Claude Sonnet 4 | GPT-5.5 Pro |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $3.00/1M tokens | $30.00/1M tokens |
| Output Price | $15.00/1M tokens | $180.00/1M tokens |
| Context Window | 200,000 tokens | 1,050,000 tokens |
| Max Output | 64,000 tokens | 128,000 tokens |
| Category | standard | reasoning |
| Capabilities | textvisioncodereasoning | textvisioncodereasoning |
| Release Date | 5/14/2025 | 4/24/2026 |
Claude Sonnet 4 vs GPT-5.5 Pro: Which Should You Choose?
Choosing between Claude Sonnet 4 and GPT-5.5 Pro depends on your priorities: cost efficiency, context length, or raw capability. Claude Sonnet 4 is the more affordable option at $3.00/1M input tokens — 90% cheaper than GPT-5.5 Pro. Meanwhile, GPT-5.5 Pro offers a significantly larger context window at 1,050,000 tokens vs 200,000 for Claude Sonnet 4.
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 is a standard model while GPT-5.5 Pro is reasoning. This means they're optimized for different workloads. GPT-5.5 Pro targets more demanding workloads, while Claude Sonnet 4 provides a cost-effective option for everyday tasks.
Output costs matter too. Claude Sonnet 4 charges $15.00/1M output tokens vs $180.00 for GPT-5.5 Pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Claude Sonnet 4 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 when:
- • Budget is a primary concern
- • You're already using Anthropic's API ecosystem
Choose GPT-5.5 Pro when:
- • You need a larger context window (1,050,000 tokens)
- • You need longer outputs (up to 128,000 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Claude Sonnet 4
- • 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
- • Smaller context window than GPT-5.5 Pro
GPT-5.5 Pro
- • Input pricing: $30.00/M tokens
- • Output pricing: $180.00/M tokens
- • Context window: 1,050,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher input cost than Claude Sonnet 4
- • Higher output cost than Claude Sonnet 4
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Sonnet 4 (Anthropic)
GPT-5.5 Pro (OpenAI)
Start using Claude Sonnet 4 today
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Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Claude Sonnet 4 or GPT-5.5 Pro?▼
What is the context window difference between Claude Sonnet 4 and GPT-5.5 Pro?▼
Which model is better for AI Agent / Agentic Workflows?▼
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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