Cheaper overall
GPT-6.1 Sol
80% lower blended rate
Higher benchmark scores
Claude Fable 5.1
leads on 6 of 8 figures
Bigger context window
GPT-6.1 Sol
1,050,000 vs 1,000,000 tokens
Cheaper cached input
GPT-6.1 Sol
$0.10 vs $0.25, 60% less
Where each one wins
GPT-6.1 Sol
- Cheaper input tokens $2.00 vs $10.00, 80% less
- Cheaper output tokens $10.00 vs $50.00, 80% less
- Cheaper cached input $0.10 vs $0.25, 60% less
- Cheaper on all four workloads
- Larger context window 1,050,000 tokens
- Higher physics research reasoning (CritPt) 31.7 vs 29.7
- Higher answer reliability (Omniscience Non-Hallucination) 45.7 vs 27.4
- Offers Flex and Priority pricing not listed for Claude Fable 5.1
Claude Fable 5.1
- Higher overall intelligence (Intelligence Index) 53.4 vs 51.8
- Higher expert-exam performance (Humanity's Last Exam) 59.1 vs 52.9
- Higher long-context reasoning (AA-LCR) 85.3 vs 83
- Ahead on 3 more benchmark figures
What four workloads cost
One run, and the same run a thousand times.
GPT-6.1 Sol is cheaper on all four workloads, by much the same margin each time — about 4.2 times, from $0.0070 against $0.0350 on a chat turn to $1.65 against $4.15 on a long document.
| Workload | GPT-6.1 Sol | Claude Fable 5.1 | ×1,000 | Difference |
|---|---|---|---|---|
| Chat turn 1,000 in / 500 out | $0.0070 | $0.0350 | $7.00 / $35.00 | GPT-6.1 Sol is 80% cheaper |
| RAG answer 10,000 in / 800 out | $0.0280 | $0.1400 | $28.00 / $140.00 | GPT-6.1 Sol is 80% cheaper |
| Agent loop 32,000 in / 700 out × 20 calls | $0.2800 | $1.25 | $280.00 / $1,250.00 | GPT-6.1 Sol is 78% cheaper |
| Long document 400,000 in / 3,000 out | $1.65 | $4.15 | $1,645.00 / $4,150.00 | GPT-6.1 Sol is 60% 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-6.1 Sol's input goes from $2.00 to $4.00. It does not change which of the two is cheaper.
| Context band | Price | GPT-6.1 Sol | Claude Fable 5.1 | Difference |
|---|---|---|---|---|
| Prompts up to 272,000 tokens | Input | $2.00 | $10.00 | GPT-6.1 Sol is 80% cheaper |
| Prompts up to 272,000 tokens | Cached input | $0.10 | $0.25 | GPT-6.1 Sol is 60% cheaper |
| Prompts up to 272,000 tokens | Output | $10.00 | $50.00 | GPT-6.1 Sol is 80% cheaper |
| Prompts over 272,000 tokens | Input | $4.00 | $10.00 | GPT-6.1 Sol is 60% cheaper |
| Prompts over 272,000 tokens | Cached input | $0.20 | $0.25 | GPT-6.1 Sol is 20% cheaper |
| Prompts over 272,000 tokens | Output | $15.00 | $50.00 | GPT-6.1 Sol is 70% cheaper |
Blended: GPT-6.1 Sol $4.00, Claude Fable 5.1 $20.00 per 1M — one rate at 3:1 input to output, for comparing two models at a glance.
GPT-6.1 Sol priced by OpenAI, Claude Fable 5.1 by Anthropic. 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-6.1 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 | GPT-6.1 Sol | Claude Fable 5.1 | Cheaper |
|---|---|---|---|
| Batch | $1.00 in / $5.00 out 50% off Standard | $5.00 in / $25.00 out 50% off Standard | GPT-6.1 Sol |
| Flex only on GPT-6.1 Sol | $1.00 in / $5.00 out 50% off Standard | Not offered | — |
| Priority only on GPT-6.1 Sol | $4.00 in / $20.00 out | Not offered | — |
Benchmarks
They share 8 figures: GPT-6.1 Sol leads on 2, Claude Fable 5.1 on 6. The widest gap is 18.3 points, on answer reliability (Omniscience Non-Hallucination).
Overall intelligence
Intelligence Index — Overall intelligence across reasoning, knowledge & math evals
Claude Fable 5.1 ahead by 1.6
Expert-exam performance
Humanity's Last Exam — Expert-level questions across many academic domains
Claude Fable 5.1 ahead by 6.2
Long-context reasoning
AA-LCR — Long-context reasoning across large inputs
Claude Fable 5.1 ahead by 2.3
Scientific coding
SciCode — Research-level scientific coding tasks
Claude Fable 5.1 ahead by 8.9
Physics research reasoning
CritPt — Unpublished physics research reasoning problems
GPT-6.1 Sol ahead by 2
Real-world task performance
GDPval — Economically valuable, real-world knowledge work
Claude Fable 5.1 ahead by 7.9
Factual accuracy
Omniscience Accuracy — Breadth of factual knowledge across domains
Claude Fable 5.1 ahead by 5.1
Answer reliability
Omniscience Non-Hallucination — How reliably the model avoids fabricated answers
GPT-6.1 Sol ahead by 18.3
Each figure is that model's best published run, with the effort level named beside it — where these scores come from.
Specifications
GPT-6.1 Sol holds 50,000 more input tokens in one request. Only GPT-6.1 Sol lists web search.
| Specification | GPT-6.1 Sol | Claude Fable 5.1 |
|---|---|---|
| Context window | 1,050,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | 128,000 tokens |
| Takes in | Text, image, file | Text, image, file |
| Puts out | Text | Text |
| Knowledge cutoff | 30 Apr 2026 | 30 Jun 2026 |
| Released | 29 Sep 2026 | 1 Sep 2026 |
| Status | Active | Active |
| Sold by | OpenAI, Perplexity | Anthropic |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Web search | Yes | Not listed |
| Prompt caching | Yes | Yes |
| Code execution | Yes | Yes |
| Computer use | Yes | Yes |
| Open weights | Not listed | Not listed |
| Reasoning | Yes | Yes |
FAQs
- Is GPT-6.1 Sol cheaper than Claude Fable 5.1?
- Yes. A 1,000-token prompt with a 500-token reply costs $0.0070 on GPT-6.1 Sol and $0.0350 on Claude Fable 5.1, and the same model is cheaper on every workload on this page.
- How much do GPT-6.1 Sol and Claude Fable 5.1 cost per 1M tokens?
- GPT-6.1 Sol costs $2.00 for input and $10.00 for output. Claude Fable 5.1 costs $10.00 and $50.00. Standard pay-as-you-go rates, as of 29 Sep 2026.
- Which is better, GPT-6.1 Sol or Claude Fable 5.1?
- On published benchmarks, Claude Fable 5.1. It leads on 6 of the 8 figures both models report, including overall intelligence (Intelligence Index), where it scores 53.4 against 51.8.
- Is Batch pricing cheaper for GPT-6.1 Sol or Claude Fable 5.1?
- Batch input costs $1.00 on GPT-6.1 Sol and $5.00 on Claude Fable 5.1, 50% below the standard rate on both.
- Does GPT-6.1 Sol or Claude Fable 5.1 have a bigger context window?
- GPT-6.1 Sol, at 1,050,000 tokens against 1,000,000. That is 50,000 more input tokens in a single request.