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Claude Opus 5.5 vs Gemini 1.5 Flash 8B

Claude Opus 5.5 leads the LLM Stats Score 59.8 to -0.8. Gemini 1.5 Flash 8B is 62.7x cheaper per token.

Anthropic · Google · Updated for 2026

Which is better?

Claude Opus 5.5 leads the overall LLM Stats Score 59.8 to -0.8, ranking #1 overall.

On price, Gemini 1.5 Flash 8B is roughly 62.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 1.5 Flash 8B also accepts a larger context window (1,048,576 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 Opus 5.5

  • overall performance matters — it scores 59.8 and ranks #1 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you want the most recent training data — it shipped Sep 2026

Choose Gemini 1.5 Flash 8B

  • cost matters — it's about 62.7x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window

At a glance

The differences that matter most.

Claude Opus 5.5
Anthropic
Gemini 1.5 Flash 8B
Google
Core performance indexes
LLM Stats Score
59.8
#1
-0.8
#335
Reasoning
57.9
#1
-0.4
#326
Cost, coverage & limits
Benchmark wins
—
—
Input price
$4.00 / M
$0.07 / M
Output price
$20.00 / M
$0.30 / M
Context window
1,000,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

3 shared
Index
Claude Opus 5.5
Gemini 1.5 Flash 8B
Math
42.5#5
2.4#293
Vision
42.9#1
-2.5#193
Multimodal
42.6#1
0.2#155
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

31 reported for Claude Opus 5.5 · 13 for Gemini 1.5 Flash 8B

No common benchmarks found

Claude Opus 5.5 and Gemini 1.5 Flash 8Bdon'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

Gemini 1.5 Flash 8B costs less

For input processing, Claude Opus 5.5 ($4.00/1M tokens) is 57.1x more expensive than Gemini 1.5 Flash 8B ($0.07/1M tokens).

For output processing, Claude Opus 5.5 ($20.00/1M tokens) is 66.7x more expensive than Gemini 1.5 Flash 8B ($0.30/1M tokens).

In conclusion, Claude Opus 5.5 is more expensive than Gemini 1.5 Flash 8B.*

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

Lowest available price from all providers
Tue Sep 22 2026 • llm-stats.com
Anthropic
Claude Opus 5.5
Input tokens$4.00
Output tokens$20.00
Best providerAnthropic
Google
Gemini 1.5 Flash 8B
Input tokens$0.07
Output tokens$0.30
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 1.5 Flash 8B accepts 1,048,576 input tokens compared to Claude Opus 5.5's 1,000,000 tokens. Claude Opus 5.5 can generate longer responses up to 128,000 tokens, while Gemini 1.5 Flash 8B is limited to 8,192 tokens.

Anthropic
Claude Opus 5.5
Input1,000,000 tokens
Output128,000 tokens
Google
Gemini 1.5 Flash 8B
Input1,048,576 tokens
Output8,192 tokens
Tue Sep 22 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Opus 5.5 and Gemini 1.5 Flash 8B support multimodal inputs.

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

Claude Opus 5.5

Text
Images
Audio
Video

Gemini 1.5 Flash 8B

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 Opus 5.5

Proprietary

Closed source

Gemini 1.5 Flash 8B

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 5.5 was released on 2026-09-22, while Gemini 1.5 Flash 8B was released on 2024-03-15.

Claude Opus 5.5 is 31 months newer than Gemini 1.5 Flash 8B.

Claude Opus 5.5

Sep 22, 2026

0 days ago

2.5yr newer
Gemini 1.5 Flash 8B

Mar 15, 2024

2.5 years ago

Knowledge Cutoff

When training data ends

Claude Opus 5.5 has a knowledge cutoff of 2026-06-01, while Gemini 1.5 Flash 8B has a cutoff of 2024-10-01.

Claude Opus 5.5 has more recent training data (up to 2026-06-01), making it potentially better informed about events through that date compared to Gemini 1.5 Flash 8B (2024-10-01).

Claude Opus 5.5

Jun 2026

1.7 yr newer
Gemini 1.5 Flash 8B

Oct 2024

Provider Availability

Claude Opus 5.5 is available from Anthropic. Gemini 1.5 Flash 8B is available from Google.

Claude Opus 5.5

anthropic logo
Anthropic
Input Price:Input: $4.00/1MOutput Price:Output: $20.00/1M

Gemini 1.5 Flash 8B

google logo
Google
Input Price:Input: $0.07/1MOutput Price:Output: $0.30/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Judge for yourself.

Run your own prompts against Claude Opus 5.5 and Gemini 1.5 Flash 8B side-by-side, then vote on the output you prefer.

Claude Opus 5.5
✓ Preferred
Gemini 1.5 Flash 8B
Open in Playground

FAQ

Common questions about Claude Opus 5.5 vs Gemini 1.5 Flash 8B.

Which is better, Claude Opus 5.5 or Gemini 1.5 Flash 8B?

Claude Opus 5.5 leads the LLM Stats Score 59.8 to -0.8. Claude Opus 5.5 is made by Anthropic and Gemini 1.5 Flash 8B is made by Google. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Claude Opus 5.5 compare to Gemini 1.5 Flash 8B in benchmarks?

Claude Opus 5.5 scores BenchCAD (with Python tool): 96.2%, Global-MMLU: 94.3%, SWE-bench Multilingual: 93.9%, MILU: 93.1%, ArXivMath: 91.2%. Gemini 1.5 Flash 8B scores XSTest: 92.6%, FLEURS: 86.4%, Natural2Code: 75.5%, WMT23: 72.6%, Video-MME: 66.2%.

Is Claude Opus 5.5 cheaper than Gemini 1.5 Flash 8B?

Gemini 1.5 Flash 8B is 57.1x cheaper for input tokens. Claude Opus 5.5 costs $4.00/M input and $20.00/M output via anthropic. Gemini 1.5 Flash 8B costs $0.07/M input and $0.30/M output via google.

What are the context window sizes for Claude Opus 5.5 and Gemini 1.5 Flash 8B?

Claude Opus 5.5 supports 1.0M tokens and Gemini 1.5 Flash 8B supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Claude Opus 5.5 and Gemini 1.5 Flash 8B?

Key differences include LLM Stats Score (59.8 vs -0.8), context window (1.0M vs 1.0M), input pricing ($4.00 vs $0.07/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 5.5 and Gemini 1.5 Flash 8B?

Claude Opus 5.5 is developed by Anthropic and Gemini 1.5 Flash 8B is developed by Google.

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