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Claude Sonnet 5.5 vs Gemini 1.5 Flash 8B

Claude Sonnet 5.5 leads the LLM Stats Score 51.5 to -0.8. Gemini 1.5 Flash 8B is 31.4x cheaper per token.

Anthropic · Google · Updated for 2026

Which is better?

Claude Sonnet 5.5 leads the overall LLM Stats Score 51.5 to -0.8, ranking #12 overall.

On price, Gemini 1.5 Flash 8B is roughly 31.4x 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 Sonnet 5.5

  • overall performance matters — it scores 51.5 and ranks #12 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 31.4x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window

At a glance

The differences that matter most.

Core performance indexes
51.5
#12
-0.8
#338
49.7
#16
-0.4
#329
Cost, coverage & limits
Benchmark wins
—
—
Input price
$2.00 / M
$0.07 / M
Output price
$10.00 / M
$0.30 / M
Context window
1,000,000
1,048,576

Individual benchmarks

8 reported for Claude Sonnet 5.5 · 13 for Gemini 1.5 Flash 8B

No common benchmarks found

Claude Sonnet 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 Sonnet 5.5 ($2.00/1M tokens) is 28.6x more expensive than Gemini 1.5 Flash 8B ($0.07/1M tokens).

For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) is 33.3x more expensive than Gemini 1.5 Flash 8B ($0.30/1M tokens).

In conclusion, Claude Sonnet 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
Mon Sep 28 2026 • llm-stats.com
Anthropic
Claude Sonnet 5.5
Input tokens$2.00
Output tokens$10.00
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 Sonnet 5.5's 1,000,000 tokens. Claude Sonnet 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 Sonnet 5.5
Input1,000,000 tokens
Output128,000 tokens
Google
Gemini 1.5 Flash 8B
Input1,048,576 tokens
Output8,192 tokens
Mon Sep 28 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude Sonnet 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 Sonnet 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 Sonnet 5.5

Proprietary

Closed source

Gemini 1.5 Flash 8B

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Sonnet 5.5 was released on 2026-09-28, while Gemini 1.5 Flash 8B was released on 2024-03-15.

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

Claude Sonnet 5.5

Sep 28, 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 Sonnet 5.5 has a knowledge cutoff of 2026-06-01, while Gemini 1.5 Flash 8B has a cutoff of 2024-10-01.

Claude Sonnet 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 Sonnet 5.5

Jun 2026

1.7 yr newer
Gemini 1.5 Flash 8B

Oct 2024

Provider Availability

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

Claude Sonnet 5.5

anthropic logo
Anthropic
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M

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 Sonnet 5.5 and Gemini 1.5 Flash 8B side-by-side, then vote on the output you prefer.

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

FAQ

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

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

Claude Sonnet 5.5 leads the LLM Stats Score 51.5 to -0.8. Claude Sonnet 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 Sonnet 5.5 compare to Gemini 1.5 Flash 8B in benchmarks?

Claude Sonnet 5.5 scores OSWorld 2.1 (partial): 80.1%, Terminal-Bench 4.0: 70.6%, Humanity's Last Exam (with tools): 64.5%, Chartography (no tools): 61.6%, GDPval-AA 2.1: 61.5%. Gemini 1.5 Flash 8B scores XSTest: 92.6%, FLEURS: 86.4%, Natural2Code: 75.5%, WMT23: 72.6%, Video-MME: 66.2%.

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

Gemini 1.5 Flash 8B is 28.6x cheaper for input tokens. Claude Sonnet 5.5 costs $2.00/M input and $10.00/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 Sonnet 5.5 and Gemini 1.5 Flash 8B?

Claude Sonnet 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 Sonnet 5.5 and Gemini 1.5 Flash 8B?

Key differences include LLM Stats Score (51.5 vs -0.8), context window (1.0M vs 1.0M), input pricing ($2.00 vs $0.07/M). See the full comparison above for benchmark-by-benchmark results.

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

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