QUICK ANSWER
● Best for hard coding and complex reasoning: Claude Fable 5 — 80.3% SWE-Bench Pro, 22 points ahead of GPT-5.5, designed for long complex tasks
● Best all-rounder and ecosystem: ChatGPT (GPT-5.5) — image gen, Advanced Voice, Codex, computer use, widest integrations
● Best price-to-performance: Gemini 3.5 Flash — $1.50/$9 per million tokens with 1M context, strong general capability
Head-to-Head Comparison
| Feature |
Claude Fable 5 |
GPT-5.5 (ChatGPT) |
Gemini 3.5 Flash |
| SWE-Bench Pro |
80.3% |
58.6% |
~50% |
| SWE-Bench Verified |
State-of-art |
88.7% |
~80% |
| API input price |
$10.00/M |
$5.00/M |
$1.50/M |
| API output price |
$50.00/M |
$20.00/M |
$9.00/M |
| Context window |
200K (128K output) |
128K |
1M tokens |
| Image generation |
✗ |
✓ DALL-E 4 |
✓ Imagen 4 |
| Voice mode |
Basic |
Advanced Voice |
Live API |
| Long autonomous tasks |
Longest of any Claude |
Goal mode (hours) |
Managed task flows |
| Safety routing |
Cyber/bio → Opus 4.8 (<5%) |
Standard filters |
Standard filters |
| Free on subscriptions |
Until June 22 only |
Included on Plus+ |
Included in Gemini |
| Available on |
Claude API, Bedrock, Copilot |
OpenAI API, Azure, AWS |
All major platforms |
Claude Fable 5 - When It Wins and When It Doesn't
Fable 5 is the first public model that can genuinely claim to be the best AI for hard engineering work. The 22-point SWE-Bench Pro lead over GPT-5.5 is not noise - it reflects a fundamental capability difference on complex multi-file real-world coding tasks. Anthropic designed Fable 5 specifically to excel as tasks get longer and more complex, and the first two days of developer testing confirm this holds in practice.
Where it doesn't win: no image generation, no Advanced Voice equivalent, $10/$50 per million tokens (5-6x more expensive than Gemini 3.5 Flash on output), and the June 22 subscription cliff means free access disappears in 11 days for Pro/Max users. The cybersecurity query routing (to Opus 4.8) means security researchers and developers working on vulnerability analysis may find Fable 5 less useful than expected in that specific domain. For the full launch details see our Claude Fable 5 launch guide.
GPT-5.5 - Still the Best All-Rounder
GPT-5.5 loses the coding crown to Fable 5 on SWE-Bench Pro. It still wins on nearly everything else. DALL-E 4 image generation is built in. Advanced Voice Mode (GPT-Realtime-2) is the best voice AI in any consumer product. Codex handles async coding on Windows and Mac with computer use and mobile remote control. The OpenAI ecosystem - plugins, memory, Operator, the widest third-party integrations - remains the reason most non-developer users stay on ChatGPT. For developers who need hard coding capability and can't afford Fable 5's pricing, compare with the Codex vs Claude Code comparison.
Gemini 3.5 Flash - The Price-Performance Champion
At $1.50 input / $9.00 output per million tokens with a 1M token context window, Gemini 3.5 Flash is the most cost-effective frontier model for high-volume workloads. It undercuts Fable 5 by 83% on output and GPT-5.5 by 55%. For applications that need strong capability but process millions of tokens per month - document analysis, content generation at scale, high-volume API calls - Gemini 3.5 Flash's unit economics are compelling. The tradeoff: SWE-Bench Pro performance trails both Fable 5 and GPT-5.5, and it lacks the deep coding specialization Fable 5 brings.
Decision Framework
Hard coding, multi-file refactors, complex engineering
Claude Fable 5 — 80.3% SWE-Bench Pro, designed to widen its lead as tasks get harder. Worth the $10/$50 price premium for high-value engineering work. Use before June 22 free window closes.
General purpose, image gen, voice, ecosystem
ChatGPT (GPT-5.5) — the safe default for non-specialist tasks. Image generation, Advanced Voice, Operator, Codex. Best single subscription for most users.
High-volume API, cost-sensitive, large documents
Gemini 3.5 Flash — $1.50/$9 with 1M context. For applications processing millions of tokens monthly where unit economics matter more than maximum capability.
Cybersecurity research and offensive security work
Note: Fable 5 routes most cybersecurity queries to Opus 4.8 via its safety classifier. If your primary use case is security research, GPT-5.5 or the direct Opus 4.8 API may give less friction.
The June 22 Factor
Fable 5 is free on Pro, Max, Team, and Enterprise plans until June 22 — then it requires usage credits. This matters for the comparison: right now Fable 5 effectively costs the same as Opus 4.8 for subscribers. After June 22, the cost difference becomes real at $10/$50 per million tokens. If you are evaluating Fable 5 against GPT-5.5, do it now while Fable 5 is free. The comparison you make today at equal cost will be different from the comparison you make on June 23 when Fable 5 is 2x the price of Opus 4.8 and 5-6x the price of Gemini 3.5 Flash.
For all model news and pricing changes as they happen, see the June 2026 AI news calendar and May 2026 archive. For the broader ChatGPT vs Claude vs Grok comparison see our three-way comparison guide.
Frequently Asked Questions
Is Claude Fable 5 better than GPT-5.5?
For hard coding and complex engineering: yes, by a significant margin (80.3% vs 58.6% SWE-Bench Pro). For general-purpose use, image generation, voice, and ecosystem breadth: GPT-5.5 still wins. For price-sensitive high-volume workloads: Gemini 3.5 Flash wins. The honest answer is they are best at different things - Fable 5 is the specialist, GPT-5.5 is the generalist.
How long is Fable 5 free on Claude subscriptions?
Until June 22, 2026 - 11 days from now. From June 23, using Fable 5 requires usage credits. Anthropic plans to restore it as a standard subscription feature once capacity scales, but no timeline has been given. Test your most important use cases against Fable 5 this week while it's free.