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Claude Haiku 5.5 vs GPT-5.1 Thinking

Claude Haiku 5.5 leads the LLM Stats Score 50.3 to 36.8. Claude Haiku 5.5 is 17.2x cheaper per token.

Anthropic · OpenAI · Updated for 2026

Which is better?

Claude Haiku 5.5 leads the overall LLM Stats Score 50.3 to 36.8, ranking #18 overall.

On price, Claude Haiku 5.5 is roughly 17.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Claude Haiku 5.5 also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.

Choose Claude Haiku 5.5

  • overall performance matters — it scores 50.3 and ranks #18 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • cost matters — it's about 17.2x cheaper per token
  • you process long inputs — it offers a 1,000,000 token context window
  • you want the most recent training data — it shipped Oct 2026

Choose GPT-5.1 Thinking

  • you want predictable pricing at $1.25/M input and $10.00/M output

At a glance

The differences that matter most.

Core performance indexes
50.3
#18
36.8
#83
47.4
#26
36.5
#85
40.7
#13
21.4
#97
Cost, coverage & limits
Benchmark wins
—
—
Input price
$0.10 / M
$1.25 / M
Output price
$0.50 / M
$10.00 / M
Context window
1,000,000
400,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Claude Haiku 5.5
GPT-5.1 Thinking
25.7#110
30.0#82
20.8#57
17.1#81
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

36 reported for Claude Haiku 5.5 · 9 for GPT-5.1 Thinking

No common benchmarks found

Claude Haiku 5.5 and GPT-5.1 Thinkingdon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Claude Haiku 5.5 costs less

For input processing, Claude Haiku 5.5 ($0.10/1M tokens) is 12.5x cheaper than GPT-5.1 Thinking ($1.25/1M tokens).

For output processing, Claude Haiku 5.5 ($0.50/1M tokens) is 20.0x cheaper than GPT-5.1 Thinking ($10.00/1M tokens).

In conclusion, GPT-5.1 Thinking is more expensive than Claude Haiku 5.5.*

* Using a 3:1 ratio of input to output tokens

Lowest available price from all providers
Wed Oct 07 2026 • llm-stats.com
Anthropic
Claude Haiku 5.5
Input tokens$0.10
Output tokens$0.50
Best providerAnthropic
OpenAI
GPT-5.1 Thinking
Input tokens$1.25
Output tokens$10.00
Best providerOpenAI
Notice missing or incorrect data?

Context Window

Maximum input and output token capacity

Claude Haiku 5.5 accepts 1,000,000 input tokens compared to GPT-5.1 Thinking's 400,000 tokens. Both models can generate responses up to 128,000 tokens.

Anthropic
Claude Haiku 5.5
Input1,000,000 tokens
Output128,000 tokens
OpenAI
GPT-5.1 Thinking
Input400,000 tokens
Output128,000 tokens
Wed Oct 07 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Haiku 5.5 and GPT-5.1 Thinking support multimodal inputs.

They are both capable of processing various types of data, offering versatility in application.

Claude Haiku 5.5

Text
Images
Audio
Video

GPT-5.1 Thinking

Text
Images
Audio
Video

License

Usage and distribution terms

Both models are licensed under proprietary licenses.

Both models have usage restrictions defined by their respective organizations.

Claude Haiku 5.5

Proprietary

Closed source

GPT-5.1 Thinking

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Haiku 5.5 was released on 2026-10-07, while GPT-5.1 Thinking was released on 2025-11-12.

Claude Haiku 5.5 is 11 months newer than GPT-5.1 Thinking.

Claude Haiku 5.5

Oct 7, 2026

0 days ago

10mo newer
GPT-5.1 Thinking

Nov 12, 2025

10 months ago

Knowledge Cutoff

When training data ends

Claude Haiku 5.5 has a documented knowledge cutoff of 2026-06-01, while GPT-5.1 Thinking's cutoff date is not specified.

We can confirm Claude Haiku 5.5's training data extends to 2026-06-01, but cannot make a direct comparison without GPT-5.1 Thinking's cutoff date.

Claude Haiku 5.5

Jun 2026

GPT-5.1 Thinking

—

Provider Availability

Claude Haiku 5.5 is available from Anthropic. GPT-5.1 Thinking is available from OpenAI.

Claude Haiku 5.5

anthropic logo
Anthropic
Input Price:Input: $0.10/1MOutput Price:Output: $0.50/1M

GPT-5.1 Thinking

openai logo
OpenAI
Input Price:Input: $1.25/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Claude Haiku 5.5 and GPT-5.1 Thinking side-by-side, then vote on the output you prefer.

Claude Haiku 5.5
✓ Preferred
GPT-5.1 Thinking
Open in Playground

FAQ

Common questions about Claude Haiku 5.5 vs GPT-5.1 Thinking.

Which is better, Claude Haiku 5.5 or GPT-5.1 Thinking?

Claude Haiku 5.5 leads the LLM Stats Score 50.3 to 36.8. Claude Haiku 5.5 is made by Anthropic and GPT-5.1 Thinking is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Haiku 5.5 compare to GPT-5.1 Thinking in benchmarks?

Claude Haiku 5.5 scores Global-MMLU: 87.8%, MILU: 87.6%, BenchCAD (with Python tool): 87.0%, Chartography: 86.2%, SWE-bench Multilingual: 83.7%. GPT-5.1 Thinking scores Tau2 Telecom: 95.6%, AIME 2025: 94.0%, BrowseComp Long Context 128k: 90.0%, GPQA: 88.1%, MMMU: 85.4%.

Is Claude Haiku 5.5 cheaper than GPT-5.1 Thinking?

Claude Haiku 5.5 is 12.5x cheaper for input tokens. Claude Haiku 5.5 costs $0.10/M input and $0.50/M output via anthropic. GPT-5.1 Thinking costs $1.25/M input and $10.00/M output via openai.

What are the context window sizes for Claude Haiku 5.5 and GPT-5.1 Thinking?

Claude Haiku 5.5 supports 1.0M tokens and GPT-5.1 Thinking supports 400K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Haiku 5.5 and GPT-5.1 Thinking?

Key differences include LLM Stats Score (50.3 vs 36.8), context window (1.0M vs 400K), input pricing ($0.10 vs $1.25/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Haiku 5.5 and GPT-5.1 Thinking?

Claude Haiku 5.5 is developed by Anthropic and GPT-5.1 Thinking is developed by OpenAI.