Claude Fable 5 vs GPT-5.5 Instant
Pricing verdict: Claude Fable 5 vs GPT-5.5 Instant: GPT-5.5 Instant is cheaper for input-heavy usage ($5.00/M vs $10.00/M input tokens), while GPT-5.5 Instant is better for long-context tasks (1,050,000 tokens).
Direct answer: choose GPT-5.5 Instant 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 right model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Claude Fable 5
GPT-5.5 Instant
Cost Differences
GPT-5.5 Instant costs less than Claude Fable 5
Quick Recommendation
Winner for direct API pricing: GPT-5.5 Instant. At the default workload, GPT-5.5 Instant saves about $45.00/month ($547.50/year) versus Claude Fable 5.
Feature Comparison
| Feature | Claude Fable 5 | GPT-5.5 Instant |
|---|---|---|
| Provider | Anthropic | OpenAI |
| Input Price | $10.00/1M tokens | $5.00/1M tokens |
| Output Price | $50.00/1M 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 | 6/9/2026 | 5/5/2026 |
Claude Fable 5 vs GPT-5.5 Instant: Which Should You Choose?
Choosing between Claude Fable 5 and GPT-5.5 Instant depends on your priorities: cost efficiency, context length, or raw capability. GPT-5.5 Instant is the more affordable option at $5.00/1M input tokens — 50% cheaper than Claude Fable 5. Meanwhile, GPT-5.5 Instant offers a significantly larger context window at 1,050,000 tokens vs 1,000,000 for Claude Fable 5.
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: GPT-5.5 Instant would save you roughly $4,500.00/month compared to Claude Fable 5. For startups and indie developers, that difference can be significant.
Output costs matter too. Claude Fable 5 charges $50.00/1M 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. GPT-5.5 Instant has the edge here at $30.00/1M 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 Fable 5 when:
- • You're already using Anthropic's API ecosystem
Choose GPT-5.5 Instant when:
- • Budget is a primary concern
- • 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 Fable 5
- • Input pricing: $10.00/M tokens
- • Output pricing: $50.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher input cost than GPT-5.5 Instant
- • Higher output cost than GPT-5.5 Instant
- • 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
- • Trade-offs are minor in this matchup.
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Claude Fable 5 (Anthropic)
GPT-5.5 Instant (OpenAI)
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Which is cheaper, Claude Fable 5 or GPT-5.5 Instant?▼
What is the context window difference between Claude Fable 5 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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