Model Comparison

Claude Opus 4.5 vs Gemini 3 FlashWhich is better in 2026?

Claude Opus 4.5 shows notably better performance in the majority of benchmarks. Gemini 3 Flash is 8.9x cheaper per token.

Verdict: Claude Opus 4.5 vs Gemini 3 Flash — which is better?

Claude Opus 4.5 (by Anthropic) and Gemini 3 Flash (by Google) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.

Claude Opus 4.5 outperforms in 4 benchmarks (ARC-AGI v2, MCP Atlas, SWE-Bench Verified, Terminal-Bench 2.0), while Gemini 3 Flash is better at 2 benchmarks (GPQA, MMMLU). Claude Opus 4.5 shows notably better performance in the majority of benchmarks.

On price, Gemini 3 Flash is roughly 8.9x 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.

Choose Claude Opus 4.5 if…

  • you want the strongest raw capability — it leads on 4 of 6 shared benchmarks

Choose Gemini 3 Flash if…

  • cost matters — it's about 8.9x 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
Want to compare interactively?Try the playground

Performance Benchmarks

Comparative analysis across standard metrics

6 benchmarks

Claude Opus 4.5 outperforms in 4 benchmarks (ARC-AGI v2, MCP Atlas, SWE-Bench Verified, Terminal-Bench 2.0), while Gemini 3 Flash is better at 2 benchmarks (GPQA, MMMLU).

Claude Opus 4.5 shows notably better performance in the majority of benchmarks.

Sat Jun 06 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3 Flash costs less

For input processing, Claude Opus 4.5 ($5.00/1M tokens) is 10.0x more expensive than Gemini 3 Flash ($0.50/1M tokens).

For output processing, Claude Opus 4.5 ($25.00/1M tokens) is 8.3x more expensive than Gemini 3 Flash ($3.00/1M tokens).

In conclusion, Claude Opus 4.5 is more expensive than Gemini 3 Flash.*

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

Lowest available price from all providers
Sat Jun 06 2026 • llm-stats.com
Anthropic
Claude Opus 4.5
Input tokens$5.00
Output tokens$25.00
Best providerAnthropic
Google
Gemini 3 Flash
Input tokens$0.50
Output tokens$3.00
Best providerGoogle
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3 Flash accepts 1,000,000 input tokens compared to Claude Opus 4.5's 200,000 tokens. Gemini 3 Flash can generate longer responses up to 65,536 tokens, while Claude Opus 4.5 is limited to 64,000 tokens.

Anthropic
Claude Opus 4.5
Input200,000 tokens
Output64,000 tokens
Google
Gemini 3 Flash
Input1,000,000 tokens
Output65,536 tokens
Sat Jun 06 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Claude Opus 4.5 and Gemini 3 Flash support multimodal inputs.

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

Claude Opus 4.5

Text
Images
Audio
Video

Gemini 3 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 Opus 4.5

Proprietary

Closed source

Gemini 3 Flash

Proprietary

Closed source

Release Timeline

When each model was launched

Claude Opus 4.5 was released on 2025-11-24, while Gemini 3 Flash was released on 2025-12-17.

Gemini 3 Flash is 1 month newer than Claude Opus 4.5.

Claude Opus 4.5

Nov 24, 2025

6 months ago

Gemini 3 Flash

Dec 17, 2025

5 months ago

3w newer

Knowledge Cutoff

When training data ends

Claude Opus 4.5 has a knowledge cutoff of 2025-03-31, while Gemini 3 Flash has a cutoff of 2025-01-31.

Claude Opus 4.5 has more recent training data (up to 2025-03-31), making it potentially better informed about events through that date compared to Gemini 3 Flash (2025-01-31).

Claude Opus 4.5

Mar 2025

2 mo newer
Gemini 3 Flash

Jan 2025

Provider Availability

Claude Opus 4.5 is available from Anthropic. Gemini 3 Flash is available from Google.

Claude Opus 4.5

anthropic logo
Anthropic
Input Price:Input: $5.00/1MOutput Price:Output: $25.00/1M

Gemini 3 Flash

google logo
Google
Input Price:Input: $0.50/1MOutput Price:Output: $3.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Anthropic
Higher ARC-AGI v2 score (37.6% vs 33.6%)
Higher MCP Atlas score (62.3% vs 57.4%)
Higher SWE-Bench Verified score (80.9% vs 78.0%)
Higher Terminal-Bench 2.0 score (59.3% vs 47.6%)
Google
Larger context window (1,000,000 tokens)
Less expensive input tokens
Less expensive output tokens
Higher GPQA score (90.4% vs 87.0%)
Higher MMMLU score (91.8% vs 90.8%)

Detailed Comparison

AI Model Comparison Table
Feature
Anthropic
Claude Opus 4.5
Google
Gemini 3 Flash

FAQ

Common questions about Claude Opus 4.5 vs Gemini 3 Flash.

Which is better, Claude Opus 4.5 or Gemini 3 Flash?

Claude Opus 4.5 shows notably better performance in the majority of benchmarks. Claude Opus 4.5 is made by Anthropic and Gemini 3 Flash is made by Google. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Claude Opus 4.5 compare to Gemini 3 Flash in benchmarks?

Claude Opus 4.5 scores Tau2 Telecom: 98.2%, MMMLU: 90.8%, Tau2 Retail: 88.9%, GPQA: 87.0%, SWE-Bench Verified: 80.9%. Gemini 3 Flash scores Vending-Bench 2: 100.0%, AIME 2025: 99.7%, Global PIQA: 92.8%, MMMLU: 91.8%, GPQA: 90.4%.

Is Claude Opus 4.5 cheaper than Gemini 3 Flash?

Gemini 3 Flash is 10.0x cheaper for input tokens. Claude Opus 4.5 costs $5.00/M input and $25.00/M output via anthropic. Gemini 3 Flash costs $0.50/M input and $3.00/M output via google.

What are the context window sizes for Claude Opus 4.5 and Gemini 3 Flash?

Claude Opus 4.5 supports 200K tokens and Gemini 3 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 Opus 4.5 and Gemini 3 Flash?

Key differences include context window (200K vs 1.0M), input pricing ($5.00 vs $0.50/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Claude Opus 4.5 and Gemini 3 Flash?

Claude Opus 4.5 is developed by Anthropic and Gemini 3 Flash is developed by Google.

Related comparisons