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Gemini 4 Carbon vs GPT-5.5 Instant

Gemini 4 Carbon leads the LLM Stats Score 59.0 to 31.7.

Google · OpenAI · Updated for 2026

Which is better?

Gemini 4 Carbon leads the overall LLM Stats Score 59.0 to 31.7, ranking #2 overall.

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

Choose Gemini 4 Carbon

  • overall performance matters — it scores 59.0 and ranks #2 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you want the most recent training data — it shipped Oct 2026

Choose GPT-5.5 Instant

  • you want predictable pricing at $5.00/M input and $30.00/M output

At a glance

The differences that matter most.

Gemini 4 Carbon
Google
GPT-5.5 Instant
OpenAI
Core performance indexes
LLM Stats Score
59.0
#2
31.7
#135
Reasoning
54.9
#5
30.5
#141
Cost, coverage & limits
Benchmark wins
—
—
Input price
— / M
$5.00 / M
Output price
— / M
$30.00 / M
Context window
—
400,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

2 shared
Index
Gemini 4 Carbon
GPT-5.5 Instant
Vision
36.0#12
21.4#83
Multimodal
38.0#6
23.3#72
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

16 reported for Gemini 4 Carbon · 9 for GPT-5.5 Instant

No common benchmarks found

Gemini 4 Carbon and GPT-5.5 Instantdon'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

Context Window

Maximum input and output token capacity

Only GPT-5.5 Instant specifies input context (400,000 tokens). Only GPT-5.5 Instant specifies output context (128,000 tokens).

Google
Gemini 4 Carbon
Input- tokens
Output- tokens
OpenAI
GPT-5.5 Instant
Input400,000 tokens
Output128,000 tokens
Thu Oct 29 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Gemini 4 Carbon and GPT-5.5 Instant support multimodal inputs.

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

Gemini 4 Carbon

Text
Images
Audio
Video

GPT-5.5 Instant

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.

Gemini 4 Carbon

Proprietary

Closed source

GPT-5.5 Instant

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 4 Carbon was released on 2026-10-28, while GPT-5.5 Instant was released on 2026-05-05.

Gemini 4 Carbon is 6 months newer than GPT-5.5 Instant.

Gemini 4 Carbon

Oct 28, 2026

1 days ago

5mo newer
GPT-5.5 Instant

May 5, 2026

5 months ago

Knowledge Cutoff

When training data ends

GPT-5.5 Instant has a documented knowledge cutoff of 2025-08-31, while Gemini 4 Carbon's cutoff date is not specified.

We can confirm GPT-5.5 Instant's training data extends to 2025-08-31, but cannot make a direct comparison without Gemini 4 Carbon's cutoff date.

Gemini 4 Carbon

—

GPT-5.5 Instant

Aug 2025

Outputs Comparison

Notice missing or incorrect data?

Judge for yourself.

Run your own prompts against Gemini 4 Carbon and GPT-5.5 Instant side-by-side, then vote on the output you prefer.

Gemini 4 Carbon
✓ Preferred
GPT-5.5 Instant
Open in Playground

FAQ

Common questions about Gemini 4 Carbon vs GPT-5.5 Instant.

Which is better, Gemini 4 Carbon or GPT-5.5 Instant?

Gemini 4 Carbon leads the LLM Stats Score 59.0 to 31.7. Gemini 4 Carbon is made by Google and GPT-5.5 Instant is made by OpenAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 4 Carbon compare to GPT-5.5 Instant in benchmarks?

Gemini 4 Carbon scores Gray Swan IPI Benchmark: 100.0%, Vending-Bench 2: 100.0%, Graphwalks BFS >128k: 96.2%, WebDev Arena: 88.4%, SEC-bench Pro: 88.2%. GPT-5.5 Instant scores HealthBench Consensus: 94.7%, OmniDocBench 1.5: 87.5%, GPQA: 85.6%, CharXiv-R: 81.6%, AIME 2025: 81.2%.

What are the context window sizes for Gemini 4 Carbon and GPT-5.5 Instant?

Gemini 4 Carbon supports an unknown number of tokens and GPT-5.5 Instant 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 Gemini 4 Carbon and GPT-5.5 Instant?

Key differences include LLM Stats Score (59.0 vs 31.7). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 4 Carbon and GPT-5.5 Instant?

Gemini 4 Carbon is developed by Google and GPT-5.5 Instant is developed by OpenAI.

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