Claude 3.5 Sonnet vs Gemini 3 Flash
Gemini 3 Flash significantly outperforms across most benchmarks. Gemini 3 Flash is 5.3x cheaper per token.
Anthropic · Google · Updated for 2026
Which is better?
Claude 3.5 Sonnet outperforms in 0 benchmarks, while Gemini 3 Flash is better at 1 benchmark (GPQA). Gemini 3 Flash significantly outperforms across most benchmarks.
On price, Gemini 3 Flash is roughly 5.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 3 Flash 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 benchmark, 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 Flash
- you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
- cost matters — it's about 5.3x 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 Dec 2025
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Claude 3.5 Sonnet outperforms in 0 benchmarks, while Gemini 3 Flash is better at 1 benchmark (GPQA).
Gemini 3 Flash significantly outperforms across most benchmarks.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude 3.5 Sonnet ($3.00/1M tokens) is 6.0x more expensive than Gemini 3 Flash ($0.50/1M tokens).
For output processing, Claude 3.5 Sonnet ($15.00/1M tokens) is 5.0x more expensive than Gemini 3 Flash ($3.00/1M tokens).
In conclusion, Claude 3.5 Sonnet is more expensive than Gemini 3 Flash.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 3 Flash accepts 1,000,000 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 Flash is limited to 65,536 tokens.
Input Capabilities
Supported data types and modalities
Both Claude 3.5 Sonnet and Gemini 3 Flash support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude 3.5 Sonnet
Gemini 3 Flash
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Claude 3.5 Sonnet was released on 2024-06-21, while Gemini 3 Flash was released on 2025-12-17.
Gemini 3 Flash is 18 months newer than Claude 3.5 Sonnet.
Jun 21, 2024
2.2 years ago
Dec 17, 2025
8 months ago
1.5yr newerKnowledge Cutoff
When training data ends
Gemini 3 Flash has a documented knowledge cutoff of 2025-01-31, while Claude 3.5 Sonnet's cutoff date is not specified.
We can confirm Gemini 3 Flash's training data extends to 2025-01-31, but cannot make a direct comparison without Claude 3.5 Sonnet's cutoff date.
—
Jan 2025
Provider Availability
Claude 3.5 Sonnet is available from Bedrock, Google. Gemini 3 Flash is available from Google.
Claude 3.5 Sonnet
Gemini 3 Flash
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude 3.5 Sonnet and Gemini 3 Flash side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude 3.5 Sonnet vs Gemini 3 Flash.