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Claude Fable 5.1 vs GPT-6 Luna Pro (batch)

Claude Fable 5.1

Anthropic

96#1
vs
Signal-by-Signal Comparison
SignalClaude Fable 5.1DeltaGPT-6 Luna Pro (batch)
Capabilities
100
--
100
Benchmarks
85
+85
0
Pricing
50
-50
100
Context window size
95
0
96
Recency
100
--
100
Output Capacity
82
--
82
Overall Result
1 wins
of 6
2 wins
GPT-6 Luna Pro (batch) wins 2 of 6 signals

Score History

Score History (7 data points)
Claude Fable 5.1GPT-6 Luna Pro (batch)
Claude Fable 5.1

95.9

current score

Leader

Claude Fable 5.1

right now

GPT-6 Luna Pro (batch)

40

current score

LMMarketCap.com
Interactive Price Comparison
100Kcalls/month
1,000tokens (~1,333 chars)
500tokens (~667 chars)

Claude Fable 5.1

Anthropic

Per request$0.035000
Daily$116.67
Monthly$3500.00
Annual$42000.00

GPT-6 Luna Pro (batch)

OpenAI

Best Value
Per request$0.000175
Daily$0.58
Monthly$17.50
Annual$210.00

GPT-6 Luna Pro (batch) saves you $3482.50/month

That's $41790.00/year compared to Claude Fable 5.1 at your current usage level of 100K calls/month.

100% cheaper
Choose GPT-6 Luna Pro (batch) for cost optimization

Claude Fable 5.1 pricing:
Input:$10.00/M tokens
Output:$50.00/M tokens
GPT-6 Luna Pro (batch) pricing:
Input:$0.05/M tokens
Output:$0.25/M tokens
Winner
Claude Fable 5.1

Anthropic

96

Composite Score

GPT-6 Luna Pro (batch)

OpenAI

40

Composite Score

Signal-by-Signal Comparison
MetricClaude Fable 5.1GPT-6 Luna Pro (batch)Winner
Overall Score
96
40
Claude Fable 5.1
Rank#1#219
Claude Fable 5.1
Quality Rank#1#219
Claude Fable 5.1
Adoption Rank#1#219
Claude Fable 5.1
Parameters------
Context Window1000K1050K
GPT-6 Luna Pro (batch)
Pricing$10.00/$50.00/M$0.05/$0.25/M--
Signal Scores
Capabilities
100
100
Claude Fable 5.1
Benchmarks
85
--
Claude Fable 5.1
Pricing
50
100
GPT-6 Luna Pro (batch)
Context window size
95
96
GPT-6 Luna Pro (batch)
Recency
100
100
Claude Fable 5.1
Output Capacity
82
82
Claude Fable 5.1
Benchmark Head-to-Head(3 benchmarks)
Claude Fable: 0GPT-6 Luna: 0
Claude Fable
GPT-6 Luna
Normalized 0-100%
GPQA Diamond
94.1%-
SWE-bench Verified
95%-
HLE
59%-
Benchmark Interpretation

Our score (0-100) is driven by benchmark performance (90%) from Arena Elo ratings, MMLU, GPQA, HumanEval, SWE-bench, and 15+ standardized evaluations. Capabilities and context window serve as tiebreakers (10%). Learn more about our methodology.

Claude Fable 5.1Elite Tier

Scores 96/100 (rank #1), placing it in the top 100% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
GPT-6 Luna Pro (batch)Entry Level

Scores 40/100 (rank #219), placing it in the top 25% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

Claude Fable 5.1 has a 56-point advantage, which typically translates to noticeably stronger performance on complex reasoning, code generation, and multi-step tasks.

When to Use Each Model

Choose Claude Fable 5.1 when you need:

  • Step-by-step reasoning and chain-of-thought problem solving

Choose GPT-6 Luna Pro (batch) when you need:

  • High-volume production workloads where API costs must be minimized
  • Step-by-step reasoning and chain-of-thought problem solving
Cost-Performance Analysis
Claude Fable 5.1
Input cost$10.00/M tokens
Output cost$50.00/M tokens
Cost per quality point$0.626
Est. monthly (1M tokens/day)$900.00
GPT-6 Luna Pro (batch)Best Value
Input cost$0.05/M tokens
Output cost$0.25/M tokens
Cost per quality point$0.007
Est. monthly (1M tokens/day)$4.50

GPT-6 Luna Pro (batch) offers 100% better value per quality point. At 1M tokens/day, you'd spend $4.50/month with GPT-6 Luna Pro (batch) vs $900.00/month with Claude Fable 5.1 - a $895.50 monthly difference.

Latency & Speed
Claude Fable 5.1Faster
Speed score0/100
GPT-6 Luna Pro (batch)
Speed score0/100

Both models have comparable response speeds. For most applications, the latency difference is negligible.

When latency matters most: Interactive chatbots, IDE code completion, real-time translation, and user-facing applications where response time directly impacts experience. For batch processing, background summarization, or offline analysis, latency is less critical.

Example Use Cases

Code generation & review

Based on overall model capabilities and architecture for coding tasks like generating functions, debugging, and refactoring

Claude Fable 5.1

Customer support chatbot

Suitable for user-facing chat with competitive response times. GPT-6 Luna Pro (batch) also offers lower per-token costs for high-volume support

Claude Fable 5.1

Long document analysis

Larger context window (1050K tokens) can process longer documents, contracts, and research papers in a single pass

GPT-6 Luna Pro (batch)

Batch data extraction

Lower output pricing ($0.25/M) reduces costs when processing thousands of records daily

GPT-6 Luna Pro (batch)

Creative writing & content

Higher overall composite score (96/100) correlates with better nuance, coherence, and style in long-form content

Claude Fable 5.1

Image understanding & OCR

Supports vision input - can analyze screenshots, diagrams, photos, and scanned documents directly

Claude Fable 5.1
Which Should You Choose?
Our recommendation:
Claude Fable 5.1

Claude Fable 5.1 clearly outperforms GPT-6 Luna Pro (batch) with a significant 55.900000000000006-point lead. For most general use cases, Claude Fable 5.1 is the stronger choice. However, GPT-6 Luna Pro (batch) may still excel in niche scenarios.

Claude Fable 5.1
Recommended

by Anthropic

  • Choose for Quality - Marginally better benchmark scores; both are excellent
  • Choose for Reliability - Higher uptime and faster response speeds
  • Choose for Prototyping - Stronger community support and better developer experience
  • Choose for Production - Wider enterprise adoption and proven at scale

by OpenAI

  • Choose for Cost - 100% lower pricing; better value at scale
Capability Comparison
CapabilityClaude Fable 5.1GPT-6 Luna Pro (batch)
Vision (Image Input)
Function Calling
Streaming
JSON Mode
Reasoning
Web Search
Image Output
Monthly Cost Calculator
1,000tokens (600 in / 400 out)
100requests/day (3,000/month)

Claude Fable 5.1

Anthropic

$78.00
estimated monthly cost

GPT-6 Luna Pro (batch)

OpenAI

Best Value
$0.3900
estimated monthly cost

GPT-6 Luna Pro (batch) saves you $77.61/month

That's 100% cheaper than Claude Fable 5.1 at 1,000 tokens/request and 100 requests/day.

Assumes 60% input / 40% output token ratio per request. Actual costs may vary based on your usage pattern.

Parameters & Context
ParameterClaude Fable 5.1GPT-6 Luna Pro (batch)
Context Window1M1.1M
Max Output Tokens128,000128,000
Open SourceNoNo
CreatedSep 1, 2026Sep 22, 2026
Last updated: 6m ago

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