Cheaper overall
gpt-5.6-sol
60% lower blended rate
Higher benchmark scores
Claude Fable 5.1
leads on 9 of 11 figures
Bigger context window
gpt-5.6-sol
1,050,000 vs 1,000,000 tokens
Cheaper cached input
Claude Fable 5.1
$0.25 vs $0.40, 38% less
Where each one wins
Claude Fable 5.1
- Cheaper cached input $0.25 vs $0.40, 38% less
- Higher overall intelligence (Intelligence Index) 53.4 vs 47
- Higher coding ability (Coding Index) 81.6 vs 78.3
- Higher multi-step tool use (Agentic Index) 57.9 vs 50.2
- Ahead on 6 more benchmark figures
gpt-5.6-sol
- Cheaper input tokens $4.00 vs $10.00, 60% less
- Cheaper output tokens $20.00 vs $50.00, 60% less
- Cheaper on all four workloads
- Larger context window 1,050,000 tokens
- Higher graduate-level science (GPQA Diamond) 94.1 vs 93.7
- Higher physics research reasoning (CritPt) 32.3 vs 29.7
- Offers Flex and Priority pricing not listed for Claude Fable 5.1
What four workloads cost
One run, and the same run a thousand times.
gpt-5.6-sol is cheaper on all four workloads, by much the same margin each time — about 2 times, from $0.0140 against $0.0350 on a chat turn to $3.29 against $4.15 on a long document.
| Workload | Claude Fable 5.1 | gpt-5.6-sol | ×1,000 | Difference |
|---|---|---|---|---|
| Chat turn 1,000 in / 500 out | $0.0350 | $0.0140 | $35.00 / $14.00 | gpt-5.6-sol is 60% cheaper |
| RAG answer 10,000 in / 800 out | $0.1400 | $0.0560 | $140.00 / $56.00 | gpt-5.6-sol is 60% cheaper |
| Agent loop 32,000 in / 700 out × 20 calls | $1.25 | $0.6800 | $1,250.00 / $680.00 | gpt-5.6-sol is 46% cheaper |
| Long document 400,000 in / 3,000 out | $4.15 | $3.29 | $4,150.00 / $3,290.00 | gpt-5.6-sol is 21% cheaper |
Price per 1M tokens
Above 272,000 input tokens the rates change, and the new rate applies to the whole request, not just the tokens past that point: gpt-5.6-sol's input goes from $4.00 to $8.00. It does not change which of the two is cheaper.
| Context band | Price | Claude Fable 5.1 | gpt-5.6-sol | Difference |
|---|---|---|---|---|
| Prompts up to 272,000 tokens | Input | $10.00 | $4.00 | gpt-5.6-sol is 60% cheaper |
| Prompts up to 272,000 tokens | Cached input | $0.25 | $0.40 | Claude Fable 5.1 is 38% cheaper |
| Prompts up to 272,000 tokens | Output | $50.00 | $20.00 | gpt-5.6-sol is 60% cheaper |
| Prompts over 272,000 tokens | Input | $10.00 | $8.00 | gpt-5.6-sol is 20% cheaper |
| Prompts over 272,000 tokens | Cached input | $0.25 | $0.80 | Claude Fable 5.1 is 69% cheaper |
| Prompts over 272,000 tokens | Output | $50.00 | $30.00 | gpt-5.6-sol is 40% cheaper |
Blended: Claude Fable 5.1 $20.00, gpt-5.6-sol $8.00 per 1M — one rate at 3:1 input to output, for comparing two models at a glance.
Claude Fable 5.1 priced by Anthropic, gpt-5.6-sol by OpenAI. Standard tier, pay-as-you-go.
Other pricing tiers
Both models offer Batch, worth up to 50% off their standard rates, and the cheaper model is the same one on every tier — so the tier you buy changes the bill rather than the choice. Only gpt-5.6-sol lists Flex and Priority, at up to 50% off its own standard rate; Claude Fable 5.1 offers none of them.
Every tier either model sells is here, so this is the whole price sheet. A saving is measured against that model's own standard rate — how we read tiers.
| Tier | Claude Fable 5.1 | gpt-5.6-sol | Cheaper |
|---|---|---|---|
| Batch | $5.00 in / $25.00 out 50% off Standard | $2.00 in / $10.00 out 50% off Standard | gpt-5.6-sol |
| Flex only on gpt-5.6-sol | Not offered | $2.00 in / $10.00 out 50% off Standard | — |
| Priority only on gpt-5.6-sol | Not offered | $8.00 in / $40.00 out | — |
Benchmarks
They share 11 figures: Claude Fable 5.1 leads on 9, gpt-5.6-sol on 2. The widest gap is 16.8 points, on answer reliability (Omniscience Non-Hallucination).
Overall intelligence
Intelligence Index — Overall intelligence across reasoning, knowledge & math evals
Claude Fable 5.1 ahead by 6.4
Coding ability
Coding Index — Coding ability across software-engineering evals
Claude Fable 5.1 ahead by 3.3
Multi-step tool use
Agentic Index — Tool use & multi-step agent task performance
Claude Fable 5.1 ahead by 7.7
Graduate-level science
GPQA Diamond — Graduate-level questions in biology, chemistry & physics
gpt-5.6-sol ahead by 0.4
Expert-exam performance
Humanity's Last Exam — Expert-level questions across many academic domains
Claude Fable 5.1 ahead by 9.6
Long-context reasoning
AA-LCR — Long-context reasoning across large inputs
Claude Fable 5.1 ahead by 1.3
Scientific coding
SciCode — Research-level scientific coding tasks
Claude Fable 5.1 ahead by 5.3
Physics research reasoning
CritPt — Unpublished physics research reasoning problems
gpt-5.6-sol ahead by 2.6
Real-world task performance
GDPval — Economically valuable, real-world knowledge work
Claude Fable 5.1 ahead by 7.3
Factual accuracy
Omniscience Accuracy — Breadth of factual knowledge across domains
Claude Fable 5.1 ahead by 7.8
Answer reliability
Omniscience Non-Hallucination — How reliably the model avoids fabricated answers
Claude Fable 5.1 ahead by 16.8
Each figure is that model's best published run, with the effort level named beside it — where these scores come from.
Specifications
gpt-5.6-sol holds 50,000 more input tokens in one request. Only Claude Fable 5.1 lists computer use.
| Specification | Claude Fable 5.1 | gpt-5.6-sol |
|---|---|---|
| Context window | 1,000,000 tokens | 1,050,000 tokens |
| Max output | 128,000 tokens | 128,000 tokens |
| Takes in | Text, image, file | Text, image, file |
| Puts out | Text | Text |
| Knowledge cutoff | 30 Jun 2026 | 16 Feb 2026 |
| Released | 1 Sep 2026 | 9 Jul 2026 |
| Status | Active | Active |
| Sold by | Anthropic | OpenAI, Perplexity |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Web search | Not listed | Not listed |
| Prompt caching | Yes | Yes |
| Code execution | Yes | Yes |
| Computer use | Yes | Not listed |
| Open weights | Not listed | Not listed |
| Reasoning | Yes | Yes |
FAQs
- Is Claude Fable 5.1 cheaper than gpt-5.6-sol?
- No — the other way round. A 1,000-token prompt with a 500-token reply costs $0.0350 on Claude Fable 5.1 and $0.0140 on gpt-5.6-sol, and the same model is cheaper on every workload on this page.
- How much do Claude Fable 5.1 and gpt-5.6-sol cost per 1M tokens?
- Claude Fable 5.1 costs $10.00 for input and $50.00 for output. gpt-5.6-sol costs $4.00 and $20.00. Standard pay-as-you-go rates, as of 1 Sep 2026.
- Which is better, Claude Fable 5.1 or gpt-5.6-sol?
- On published benchmarks, Claude Fable 5.1. It leads on 9 of the 11 figures both models report, including overall intelligence (Intelligence Index), where it scores 53.4 against 47.
- Is Batch pricing cheaper for Claude Fable 5.1 or gpt-5.6-sol?
- Batch input costs $5.00 on Claude Fable 5.1 and $2.00 on gpt-5.6-sol, 50% below the standard rate on both.
- Does Claude Fable 5.1 or gpt-5.6-sol have a bigger context window?
- gpt-5.6-sol, at 1,050,000 tokens against 1,000,000. That is 50,000 more input tokens in a single request.