Claude Opus 4.6 vs GPT-5.5 Instant
Pricing verdict: Claude Opus 4.6 vs GPT-5.5 Instant: Claude Opus 4.6 is cheaper for input-heavy usage ($5.00/M vs $5.00/M input tokens), while GPT-5.5 Instant is better for long-context tasks (1,050,000 tokens).
Direct answer: choose Claude Opus 4.6 for lower token spend and choose GPT-5.5 Instant when your workload needs longer context.
Compare API pricing, input and output token costs, context windows, and monthly estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Opus 4.6
GPT-5.5 Instant
Cost Differences
GPT-5.5 Instant costs more than Claude Opus 4.6
Quick Recommendation
Winner for direct API pricing: Claude Opus 4.6. At the default workload, Claude Opus 4.6 saves about $7.50/month ($91.25/year) versus GPT-5.5 Instant.
Feature Comparison
| Feature | Claude Opus 4.6 | GPT-5.5 Instant |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $5.00/1M tokens | $5.00/1M tokens |
| Output Price | $25.00/1M tokens | $30.00/1M tokens |
| Context Window | 1,000,000 tokens | 1,050,000 tokens |
| Max Output | 128,000 tokens | 128,000 tokens |
| Category | flagship | flagship |
| Capabilities | textvisionreasoningcode | textvisioncodereasoning |
| Release Date | 2/5/2026 | 5/5/2026 |
Claude Opus 4.6 vs GPT-5.5 Instant: Which Should You Choose?
Choosing between Claude Opus 4.6 and GPT-5.5 Instant depends on your priorities: cost efficiency, context length, or raw capability. Claude Opus 4.6 is the more affordable option at $5.00/1M input tokens. Meanwhile, GPT-5.5 Instant offers a significantly larger context window at 1,050,000 tokens vs 1,000,000 for Claude Opus 4.6.
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.
Both models are in the flagship category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: Claude Opus 4.6 would save you roughly $750.00/month compared to GPT-5.5 Instant. For startups and indie developers, that difference can be significant.
Output costs matter too. Claude Opus 4.6 charges $25.00/1M output tokens vs $30.00 for GPT-5.5 Instant. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Claude Opus 4.6 has the edge here at $25.00/1M 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 Opus 4.6 when:
- • You're already using Anthropic's API ecosystem
Choose GPT-5.5 Instant when:
- • You need a larger context window (1,050,000 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Claude Opus 4.6
- • Input pricing: $5.00/M tokens
- • Output pricing: $25.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Smaller context window than GPT-5.5 Instant
GPT-5.5 Instant
- • Input pricing: $5.00/M tokens
- • Output pricing: $30.00/M tokens
- • Context window: 1,050,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher output cost than Claude Opus 4.6
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Opus 4.6 (Anthropic)
GPT-5.5 Instant (OpenAI)
Start using Claude Opus 4.6 today
Sign Up for Anthropic →Start using GPT-5.5 Instant today
Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Claude Opus 4.6 or GPT-5.5 Instant?▼
What is the context window difference between Claude Opus 4.6 and GPT-5.5 Instant?▼
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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