Claude Fable 5 vs GPT-5.5
Anthropic's frontier flagship against OpenAI's flagship — published pricing, context windows and specs, side by side.
Claude Fable 5 vs GPT-5.5: side-by-side
| Claude Fable 5 | GPT-5.5 | |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Released | 9 June 2026 · back globally 1 July 2026 | 23 April 2026 |
| Tier | Frontier flagship | Flagship |
| Context window | 1,000,000 tokens (default & max) | 1,000,000 tokens (400K in Codex CLI) |
| Max output | Up to 128,000 tokens | Not specified |
| API price (per 1M) | $10 / $50 per 1M tokens | $5 / $30 per 1M tokens (Thinking) |
| Access | Proprietary — Claude API, claude.ai, Claude Code, AWS Bedrock, Google Cloud, Microsoft Foundry | Proprietary — ChatGPT & Codex (Plus, Pro, Business, Enterprise) + API |
| Best at | Hardest reasoning and agentic tasks | Agentic coding, computer use, deep research |
| Standout | Anthropic's most capable released model; falls back to Opus 4.8 on some topics (<5% of sessions) | First full retrain since GPT-4.5 — unified multimodal (text, images, audio, video) |
Price comparison
| Model | Input (per 1M) | Output (per 1M) |
|---|---|---|
| Claude Fable 5 | $10.00 | $50.00 |
| GPT-5.5 (Thinking) | $5.00 | $30.00 |
| GPT-5.5 Pro | $30.00 | $180.00 |
Estimate your monthly API cost for Claude Fable 5 vs GPT-5.5 with the LLM API pricing calculator →
Published benchmark figures
Each figure below is the model's own published score as listed on its AI Model Hub page. Different suites (and suite versions) are not directly comparable.
| Model | Benchmark | Published score |
|---|---|---|
| GPT-5.5 | Terminal-Bench 2.0 | 82.7% |
| GPT-5.5 | GDPval | 84.9% |
| GPT-5.5 | Expert-SWE | 73.1% |
| GPT-5.5 | SWE-bench Pro | 58.6% |
| GPT-5.5 | FrontierMath Tier 4 | 35.4% |
What the table says
- Pricing. Claude Fable 5 lists at $10 / $50 per 1M tokens; GPT-5.5 lists at $5 / $30 per 1M tokens (Thinking). On these published rates, GPT-5.5's input price is 2x lower than Claude Fable 5's, and GPT-5.5's output price is 1.7x lower than Claude Fable 5's. GPT-5.5 Pro lists at $30 / $180 per 1M tokens.
- Context. Both are in the same context class: Claude Fable 5 lists 1,000,000 tokens (default & max) and GPT-5.5 lists 1,000,000 tokens (400K in Codex CLI).
- Access. Both are proprietary, hosted-API models; neither publishes weights for self-hosting.
- Benchmarks. The two model pages report results on different benchmark suites, so the published scores are not directly comparable head-to-head; the tables below list each model's own published figures.
Key takeaway
Everything above is drawn from the two models' published rate cards and spec sheets. Which one fits depends on the workload you price it against — run your own token volumes through the pricing calculator to see the monthly difference.
Full Claude Fable 5 overview Full GPT-5.5 overview
Frequently asked questions
Which is cheaper, Claude Fable 5 or GPT-5.5?
GPT-5.5 — it lists at $5 / $30 per 1M tokens (Thinking) versus $10 / $50 per 1M tokens for Claude Fable 5.
Which has the bigger context window, Claude Fable 5 or GPT-5.5?
They are in the same class: Claude Fable 5 lists 1,000,000 tokens (default & max) and GPT-5.5 lists 1,000,000 tokens (400K in Codex CLI).
Which model is newer?
Claude Fable 5 is the more recent release (9 June 2026 · back globally 1 July 2026); GPT-5.5 was released 23 April 2026.
Can I run Claude Fable 5 or GPT-5.5 locally?
No — both Claude Fable 5 and GPT-5.5 are proprietary models accessed through their vendors' APIs and apps; neither publishes weights.
Related comparisons
- Claude Sonnet 5 vs GPT-5.5 →
- Claude Fable 5 vs Claude Opus 4.8 →
- GPT-5.5 vs Gemini 3.1 →
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