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Claude Sonnet 4.5 vs GPT-5.6 Luna (batch)

Claude Sonnet 4.5

Anthropic

82#74
vs
Signal-by-Signal Comparison
SignalClaude Sonnet 4.5DeltaGPT-5.6 Luna (batch)
Capabilities
100
--
100
Benchmarks
82
-6
88
Pricing
85
-14
99
Context window size
95
0
96
Recency
76
-24
100
Output Capacity
80
-5
85
Overall Result
0 wins
of 6
5 wins
GPT-5.6 Luna (batch) wins 5 of 6 signals

Score History

Score History (25 data points)
Claude Sonnet 4.5GPT-5.6 Luna (batch)
Claude Sonnet 4.5

82.4

current score

Leader

GPT-5.6 Luna (batch)

right now

GPT-5.6 Luna (batch)

89

current score

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

Claude Sonnet 4.5

Anthropic

Per request$0.010500
Daily$35.00
Monthly$1050.00
Annual$12600.00

GPT-5.6 Luna (batch)

OpenAI

Best Value
Per request$0.000400
Daily$1.33
Monthly$40.00
Annual$480.00

GPT-5.6 Luna (batch) saves you $1010.00/month

That's $12120.00/year compared to Claude Sonnet 4.5 at your current usage level of 100K calls/month.

96% cheaper
Choose GPT-5.6 Luna (batch) for cost optimization

Claude Sonnet 4.5 pricing:
Input:$3.00/M tokens
Output:$15.00/M tokens
GPT-5.6 Luna (batch) pricing:
Input:$0.10/M tokens
Output:$0.60/M tokens
Claude Sonnet 4.5

Anthropic

82

Composite Score

Winner
GPT-5.6 Luna (batch)

OpenAI

89

Composite Score

Signal-by-Signal Comparison
MetricClaude Sonnet 4.5GPT-5.6 Luna (batch)Winner
Overall Score
82
89
GPT-5.6 Luna (batch)
Rank#74#35
GPT-5.6 Luna (batch)
Quality Rank#74#35
GPT-5.6 Luna (batch)
Adoption Rank#74#35
GPT-5.6 Luna (batch)
Parameters------
Context Window1000K1050K
GPT-5.6 Luna (batch)
Pricing$3.00/$15.00/M$0.10/$0.60/M--
Signal Scores
Capabilities
100
100
Claude Sonnet 4.5
Benchmarks
82
88
GPT-5.6 Luna (batch)
Pricing
85
99
GPT-5.6 Luna (batch)
Context window size
95
96
GPT-5.6 Luna (batch)
Recency
76
100
GPT-5.6 Luna (batch)
Output Capacity
80
85
GPT-5.6 Luna (batch)
Benchmark Head-to-Head(12 benchmarks)
Claude Sonnet: 1GPT-5.6 Luna: 10
Claude Sonnet
GPT-5.6 Luna
Normalized 0-100%
MMLU
90.8%93%
MMLU-Pro
76.5%84.5%
GPQA Diamond
83.4%85%
MATH-500
83%92.5%
HumanEval
94.5%96.5%
SWE-bench Verified
77.2%75%
AIME 2024
60%-
IFEval
90.2%92%
BBH
88.5%90.5%
Arena Elo
14521465
LiveBench
70.5%76%
HLE
13.72%35%
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 Sonnet 4.5Strong Performer

Scores 82/100 (rank #74), placing it in the top 75% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
GPT-5.6 Luna (batch)Elite Tier

Scores 89/100 (rank #35), placing it in the top 88% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

GPT-5.6 Luna (batch) has a 7-point advantage, which typically translates to noticeably better performance on complex reasoning, code generation, and multi-step tasks.

When to Use Each Model

Choose Claude Sonnet 4.5 when you need:

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

Choose GPT-5.6 Luna (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 Sonnet 4.5
Input cost$3.00/M tokens
Output cost$15.00/M tokens
Cost per quality point$0.218
Est. monthly (1M tokens/day)$270.00
GPT-5.6 Luna (batch)Best Value
Input cost$0.10/M tokens
Output cost$0.60/M tokens
Cost per quality point$0.008
Est. monthly (1M tokens/day)$10.50

GPT-5.6 Luna (batch) offers 96% better value per quality point. At 1M tokens/day, you'd spend $10.50/month with GPT-5.6 Luna (batch) vs $270.00/month with Claude Sonnet 4.5 - a $259.50 monthly difference.

Latency & Speed
Claude Sonnet 4.5Faster
Speed score0/100
GPT-5.6 Luna (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 Sonnet 4.5

Customer support chatbot

Suitable for user-facing chat with competitive response times. GPT-5.6 Luna (batch) also offers lower per-token costs for high-volume support

Claude Sonnet 4.5

Long document analysis

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

GPT-5.6 Luna (batch)

Batch data extraction

Lower output pricing ($0.60/M) reduces costs when processing thousands of records daily

GPT-5.6 Luna (batch)

Creative writing & content

Higher overall composite score (89/100) correlates with better nuance, coherence, and style in long-form content

GPT-5.6 Luna (batch)

Image understanding & OCR

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

Claude Sonnet 4.5
Which Should You Choose?
Our recommendation:
GPT-5.6 Luna (batch)

GPT-5.6 Luna (batch) has a moderate advantage with a 6.599999999999994-point lead in composite score. It wins on more signal dimensions, but Claude Sonnet 4.5 has specific strengths that could make it the better choice for certain workflows.

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 - 96% lower pricing; better value at scale
Capability Comparison
CapabilityClaude Sonnet 4.5GPT-5.6 Luna (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 Sonnet 4.5

Anthropic

$23.40
estimated monthly cost

GPT-5.6 Luna (batch)

OpenAI

Best Value
$0.9000
estimated monthly cost

GPT-5.6 Luna (batch) saves you $22.50/month

That's 96% cheaper than Claude Sonnet 4.5 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 Sonnet 4.5GPT-5.6 Luna (batch)
Context Window1M1.1M
Max Output Tokens64,000128,000
Open SourceNoNo
CreatedSep 29, 2025Jul 9, 2026
Last updated: 27m ago

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