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Claude 3.5 Sonnet vs Gemini 3.8 Flash

Gemini 3.8 Flash leads the LLM Stats Score 51.3 to 19.3. Gemini 3.8 Flash is 4.0x cheaper per token.

Anthropic · Google · Updated for 2026

Which is better?

Gemini 3.8 Flash leads the overall LLM Stats Score 51.3 to 19.3, ranking #14 overall.

On price, Gemini 3.8 Flash is roughly 4.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.8 Flash 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 3.5 Sonnet

  • you want predictable pricing at $3.00/M input and $15.00/M output

Choose Gemini 3.8 Flash

  • overall performance matters — it scores 51.3 and ranks #14 on LLM Stats
  • your work emphasizes reasoning and coding — it leads those capability indexes
  • cost matters — it's about 4.0x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Sep 2026

At a glance

The differences that matter most.

Claude 3.5 Sonnet
Anthropic
Gemini 3.8 Flash
Google
Core performance indexes
LLM Stats Score
19.3
#195
51.3
#14
Reasoning
20.3
#178
47.2
#23
Coding
11.7
#146
39.9
#12
Cost, coverage & limits
Benchmark wins
—
—
Input price
$3.00 / M
$0.75 / M
Output price
$15.00 / M
$3.75 / M
Context window
200,000
1,048,576

Capability indexes

Additional strengths measured across groups of related public benchmarks

3 shared
Index
Claude 3.5 Sonnet
Gemini 3.8 Flash
Vision
14.9#86
34.0#12
Tool use
8.6#131
26.9#24
Multimodal
18.2#69
35.0#11
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

19 reported for Claude 3.5 Sonnet · 13 for Gemini 3.8 Flash

No common benchmarks found

Claude 3.5 Sonnet and Gemini 3.8 Flashdon'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 3.8 Flash costs less

For input processing, Claude 3.5 Sonnet ($3.00/1M tokens) is 4.0x more expensive than Gemini 3.8 Flash ($0.75/1M tokens).

For output processing, Claude 3.5 Sonnet ($15.00/1M tokens) is 4.0x more expensive than Gemini 3.8 Flash ($3.75/1M tokens).

In conclusion, Claude 3.5 Sonnet is more expensive than Gemini 3.8 Flash.*

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

Lowest available price from all providers
Wed Sep 02 2026 • llm-stats.com
Anthropic
Claude 3.5 Sonnet
Input tokens$3.00
Output tokens$15.00
Best providerAnthropic
Google
Gemini 3.8 Flash
Input tokens$0.75
Output tokens$3.75
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.8 Flash accepts 1,048,576 input tokens compared to Claude 3.5 Sonnet's 200,000 tokens. Claude 3.5 Sonnet can generate longer responses up to 200,000 tokens, while Gemini 3.8 Flash is limited to 65,536 tokens.

Anthropic
Claude 3.5 Sonnet
Input200,000 tokens
Output200,000 tokens
Google
Gemini 3.8 Flash
Input1,048,576 tokens
Output65,536 tokens
Wed Sep 02 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Claude 3.5 Sonnet and Gemini 3.8 Flash support multimodal inputs.

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

Claude 3.5 Sonnet

Text
Images
Audio
Video

Gemini 3.8 Flash

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 3.5 Sonnet

Proprietary

Closed source

Gemini 3.8 Flash

Proprietary

Closed source

Release Timeline

When each model was launched

Claude 3.5 Sonnet was released on 2024-10-22, while Gemini 3.8 Flash was released on 2026-09-02.

Gemini 3.8 Flash is 23 months newer than Claude 3.5 Sonnet.

Claude 3.5 Sonnet

Oct 22, 2024

1.9 years ago

Gemini 3.8 Flash

Sep 2, 2026

0 days ago

1.9yr newer

Knowledge Cutoff

When training data ends

Gemini 3.8 Flash has a documented knowledge cutoff of 2026-03-31, while Claude 3.5 Sonnet's cutoff date is not specified.

We can confirm Gemini 3.8 Flash's training data extends to 2026-03-31, but cannot make a direct comparison without Claude 3.5 Sonnet's cutoff date.

Claude 3.5 Sonnet

—

Gemini 3.8 Flash

Mar 2026

Provider Availability

Claude 3.5 Sonnet is available from Anthropic, Bedrock, Google. Gemini 3.8 Flash is available from Google.

Claude 3.5 Sonnet

anthropic logo
Anthropic
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
bedrock logo
AWS Bedrock
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M
google logo
Google
Input Price:Input: $3.00/1MOutput Price:Output: $15.00/1M

Gemini 3.8 Flash

google logo
Google
Input Price:Input: $0.75/1MOutput Price:Output: $3.75/1M
* 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 3.5 Sonnet and Gemini 3.8 Flash side-by-side, then vote on the output you prefer.

Claude 3.5 Sonnet
✓ Preferred
Gemini 3.8 Flash
Open in Playground

FAQ

Common questions about Claude 3.5 Sonnet vs Gemini 3.8 Flash.

Which is better, Claude 3.5 Sonnet or Gemini 3.8 Flash?

Gemini 3.8 Flash leads the LLM Stats Score 51.3 to 19.3. Claude 3.5 Sonnet is made by Anthropic and Gemini 3.8 Flash 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 3.5 Sonnet compare to Gemini 3.8 Flash in benchmarks?

Claude 3.5 Sonnet scores GSM8k: 96.4%, DocVQA: 95.2%, AI2D: 94.7%, HumanEval: 93.7%, BIG-Bench Hard: 93.1%. Gemini 3.8 Flash scores Terminal-Bench 2.1: 89.4%, LVBench: 87.1%, CharXiv-R: 86.2%, LABBench2: 86.2%, DeepSWE 1.1: 73.7%.

Is Claude 3.5 Sonnet cheaper than Gemini 3.8 Flash?

Gemini 3.8 Flash is 4.0x cheaper for input tokens. Claude 3.5 Sonnet costs $3.00/M input and $15.00/M output via anthropic. Gemini 3.8 Flash costs $0.75/M input and $3.75/M output via google.

What are the context window sizes for Claude 3.5 Sonnet and Gemini 3.8 Flash?

Claude 3.5 Sonnet supports 200K tokens and Gemini 3.8 Flash 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 3.5 Sonnet and Gemini 3.8 Flash?

Key differences include LLM Stats Score (19.3 vs 51.3), context window (200K vs 1.0M), input pricing ($3.00 vs $0.75/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude 3.5 Sonnet and Gemini 3.8 Flash?

Claude 3.5 Sonnet is developed by Anthropic and Gemini 3.8 Flash is developed by Google.

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