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Claude Opus 4.5 vs GPT-5.1 Chat

Claude Opus 4.5

Anthropic

85#35
vs
GPT-5.1 Chat

OpenAI

86#33
Signal-by-Signal Comparison
SignalClaude Opus 4.5DeltaGPT-5.1 Chat
Capabilities
100
+17
83
Benchmarks
85
-4
88
Pricing
75
-15
90
Context window size
76
+3
73
Recency
92
+2
90
Output Capacity
80
+5
75
Overall Result
4 wins
of 6
2 wins
Claude Opus 4.5 wins 4 of 6 signals

Score History

Score History (21 data points)
Claude Opus 4.5GPT-5.1 Chat
Claude Opus 4.5

84.7

current score

Leader

GPT-5.1 Chat

right now

GPT-5.1 Chat

86.2

current score

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

Claude Opus 4.5

Anthropic

Per request$0.017500
Daily$58.33
Monthly$1750.00
Annual$21000.00

GPT-5.1 Chat

OpenAI

Best Value
Per request$0.006250
Daily$20.83
Monthly$625.00
Annual$7500.00

GPT-5.1 Chat saves you $1125.00/month

That's $13500.00/year compared to Claude Opus 4.5 at your current usage level of 100K calls/month.

64% cheaper
Choose GPT-5.1 Chat for cost optimization

Claude Opus 4.5 pricing:
Input:$5.00/M tokens
Output:$25.00/M tokens
GPT-5.1 Chat pricing:
Input:$1.25/M tokens
Output:$10.00/M tokens
Claude Opus 4.5

Anthropic

85

Composite Score

Winner
GPT-5.1 Chat

OpenAI

86

Composite Score

Signal-by-Signal Comparison
MetricClaude Opus 4.5GPT-5.1 ChatWinner
Overall Score
85
86
GPT-5.1 Chat
Rank#35#33
GPT-5.1 Chat
Quality Rank#35#33
GPT-5.1 Chat
Adoption Rank#35#33
GPT-5.1 Chat
Parameters------
Context Window200K128K
Claude Opus 4.5
Pricing$5.00/$25.00/M$1.25/$10.00/M--
Signal Scores
Capabilities
100
83
Claude Opus 4.5
Benchmarks
85
88
GPT-5.1 Chat
Pricing
75
90
GPT-5.1 Chat
Context window size
76
73
Claude Opus 4.5
Recency
92
90
Claude Opus 4.5
Output Capacity
80
75
Claude Opus 4.5
Benchmark Head-to-Head(12 benchmarks)
Claude Opus: 21 tiesGPT-5.1 Chat: 8
Claude Opus
GPT-5.1 Chat
Normalized 0-100%
MMLU
91.4%93.2%
MMLU-Pro
78%85%
GPQA Diamond
86.2%86.5%
MATH-500
88.1%93.5%
HumanEval
95.2%96.8%
SWE-bench Verified
80.9%76.5%
AIME 2024
72%-
IFEval
91.5%92.5%
BBH
90%91%
Arena Elo
14301475
LiveBench
74%74%
HLE
32.1%23.68%
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 Opus 4.5Strong Performer

Scores 85/100 (rank #35), placing it in the top 88% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100
GPT-5.1 ChatElite Tier

Scores 86/100 (rank #33), placing it in the top 89% of all 290 models tracked.

Raw Quality0/100
Cost Efficiency0/100
Speed0/100

With only a 2-point gap, these models are in the same performance tier. The practical difference in output quality is minimal - your choice should depend on pricing, latency requirements, and specific feature needs.

When to Use Each Model

Choose Claude Opus 4.5 when you need:

  • Processing long documents or large codebases (200K token context)
  • Step-by-step reasoning and chain-of-thought problem solving

Choose GPT-5.1 Chat when you need:

  • High-volume production workloads where API costs must be minimized
Cost-Performance Analysis
Claude Opus 4.5
Input cost$5.00/M tokens
Output cost$25.00/M tokens
Cost per quality point$0.354
Est. monthly (1M tokens/day)$450.00
GPT-5.1 ChatBest Value
Input cost$1.25/M tokens
Output cost$10.00/M tokens
Cost per quality point$0.131
Est. monthly (1M tokens/day)$168.75

GPT-5.1 Chat offers 63% better value per quality point. At 1M tokens/day, you'd spend $168.75/month with GPT-5.1 Chat vs $450.00/month with Claude Opus 4.5 - a $281.25 monthly difference.

Latency & Speed
Claude Opus 4.5Faster
Speed score0/100
GPT-5.1 Chat
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 Opus 4.5

Customer support chatbot

Suitable for user-facing chat with competitive response times. GPT-5.1 Chat also offers lower per-token costs for high-volume support

Claude Opus 4.5

Long document analysis

Larger context window (200K tokens) can process longer documents, contracts, and research papers in a single pass

Claude Opus 4.5

Batch data extraction

Lower output pricing ($10.00/M) reduces costs when processing thousands of records daily

GPT-5.1 Chat

Creative writing & content

Higher overall composite score (86/100) correlates with better nuance, coherence, and style in long-form content

GPT-5.1 Chat

Image understanding & OCR

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

Claude Opus 4.5
Which Should You Choose?
Our recommendation:
GPT-5.1 Chat

Claude Opus 4.5 and GPT-5.1 Chat are extremely close in overall performance (only 1.5 points apart). Your best choice depends entirely on which specific strengths matter most for your use case.

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
GPT-5.1 Chat
Recommended

by OpenAI

  • Choose for Cost - 63% lower pricing; better value at scale
Capability Comparison
CapabilityClaude Opus 4.5GPT-5.1 Chat
Vision (Image Input)
Function Calling
Streaming
JSON Mode
Reasoningdiffers
Web Search
Image Output
Monthly Cost Calculator
1,000tokens (600 in / 400 out)
100requests/day (3,000/month)

Claude Opus 4.5

Anthropic

$39.00
estimated monthly cost

GPT-5.1 Chat

OpenAI

Best Value
$14.25
estimated monthly cost

GPT-5.1 Chat saves you $24.75/month

That's 63% cheaper than Claude Opus 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 Opus 4.5GPT-5.1 Chat
Context Window200K128K
Max Output Tokens64,00032,000
Open SourceNoNo
CreatedNov 24, 2025Nov 13, 2025
Last updated: 14m ago

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