Model Comparison

Gemini 3.5 Flash vs GPT-5.5Which is better in 2026?

GPT-5.5 shows notably better performance in the majority of benchmarks. Gemini 3.5 Flash is 3.3x cheaper per token.

Verdict: Gemini 3.5 Flash vs GPT-5.5 — which is better?

Gemini 3.5 Flash (by Google) and GPT-5.5 (by OpenAI) 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.

Gemini 3.5 Flash outperforms in 5 benchmarks (Finance Agent v2, GDPval-AA, MCP Atlas, MMMU-Pro, Toolathlon), while GPT-5.5 is better at 9 benchmarks (ARC-AGI v2, Finance Agent, Humanity's Last Exam, Legal Agent Benchmark, LiveBench, MRCR v2 (8-needle), OSWorld-Verified, SWE-Bench Pro, Terminal-Bench 2.0). GPT-5.5 shows notably better performance in the majority of benchmarks.

On price, Gemini 3.5 Flash is roughly 3.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

GPT-5.5 also accepts a larger context window (1,050,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Gemini 3.5 Flash if…

  • cost matters — it's about 3.3x cheaper per token
  • you want the most recent training data — it shipped May 2026

Choose GPT-5.5 if…

  • you want the strongest raw capability — it leads on 9 of 14 shared benchmarks
  • you process long inputs — it offers a 1,050,000 token context window

Performance Benchmarks

Comparative analysis across standard metrics

14 benchmarks

Gemini 3.5 Flash outperforms in 5 benchmarks (Finance Agent v2, GDPval-AA, MCP Atlas, MMMU-Pro, Toolathlon), while GPT-5.5 is better at 9 benchmarks (ARC-AGI v2, Finance Agent, Humanity's Last Exam, Legal Agent Benchmark, LiveBench, MRCR v2 (8-needle), OSWorld-Verified, SWE-Bench Pro, Terminal-Bench 2.0).

GPT-5.5 shows notably better performance in the majority of benchmarks.

Fri Jul 17 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3.5 Flash costs less

For input processing, Gemini 3.5 Flash ($1.50/1M tokens) is 3.3x cheaper than GPT-5.5 ($5.00/1M tokens).

For output processing, Gemini 3.5 Flash ($9.00/1M tokens) is 3.3x cheaper than GPT-5.5 ($30.00/1M tokens).

In conclusion, GPT-5.5 is more expensive than Gemini 3.5 Flash.*

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

Lowest available price from all providers
Fri Jul 17 2026 • llm-stats.com
Google
Gemini 3.5 Flash
Input tokens$1.50
Output tokens$9.00
Best providerGoogle
OpenAI
GPT-5.5
Input tokens$5.00
Output tokens$30.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

GPT-5.5 accepts 1,050,000 input tokens compared to Gemini 3.5 Flash's 1,048,576 tokens. GPT-5.5 can generate longer responses up to 128,000 tokens, while Gemini 3.5 Flash is limited to 65,536 tokens.

Google
Gemini 3.5 Flash
Input1,048,576 tokens
Output65,536 tokens
OpenAI
GPT-5.5
Input1,050,000 tokens
Output128,000 tokens
Fri Jul 17 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.5 Flash and GPT-5.5 support multimodal inputs.

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

Gemini 3.5 Flash

Text
Images
Audio
Video

GPT-5.5

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.

Gemini 3.5 Flash

Proprietary

Closed source

GPT-5.5

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.5 Flash was released on 2026-05-19, while GPT-5.5 was released on 2026-04-23.

Gemini 3.5 Flash is 1 month newer than GPT-5.5.

Gemini 3.5 Flash

May 19, 2026

1 months ago

3w newer
GPT-5.5

Apr 23, 2026

2 months ago

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash has a knowledge cutoff of 2026-01-31, while GPT-5.5 has a cutoff of 2025-12-01.

Gemini 3.5 Flash has more recent training data (up to 2026-01-31), making it potentially better informed about events through that date compared to GPT-5.5 (2025-12-01).

Gemini 3.5 Flash

Jan 2026

1 mo newer
GPT-5.5

Dec 2025

Provider Availability

Gemini 3.5 Flash is available from Google. GPT-5.5 is available from OpenAI.

Gemini 3.5 Flash

google logo
Google
Input Price:Input: $1.50/1MOutput Price:Output: $9.00/1M

GPT-5.5

openai logo
OpenAI
Input Price:Input: $5.00/1MOutput Price:Output: $30.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Less expensive input tokens
Less expensive output tokens
Higher Finance Agent v2 score (57.9% vs 51.8%)
Higher GDPval-AA score (45.7% vs 37.8%)
Higher MCP Atlas score (83.6% vs 75.3%)
Higher MMMU-Pro score (83.6% vs 83.2%)
Higher Toolathlon score (56.5% vs 55.6%)
OpenAI
Larger context window (1,050,000 tokens)
Higher ARC-AGI v2 score (85.0% vs 72.1%)
Higher Finance Agent score (60.0% vs 57.9%)
Higher Humanity's Last Exam score (52.2% vs 40.2%)
Higher Legal Agent Benchmark score (2.1% vs 0.8%)
Higher LiveBench score (80.7% vs 75.0%)
Higher MRCR v2 (8-needle) score (74.0% vs 26.6%)
Higher OSWorld-Verified score (78.7% vs 78.4%)
Higher SWE-Bench Pro score (58.6% vs 55.1%)
Higher Terminal-Bench 2.0 score (82.7% vs 76.2%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemini 3.5 Flash and GPT-5.5 side-by-side, then vote on the output you prefer.

Gemini 3.5 Flash
✓ Preferred
GPT-5.5
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.5 Flash
OpenAI
GPT-5.5

FAQ

Common questions about Gemini 3.5 Flash vs GPT-5.5.

Which is better, Gemini 3.5 Flash or GPT-5.5?

GPT-5.5 shows notably better performance in the majority of benchmarks. Gemini 3.5 Flash is made by Google and GPT-5.5 is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemini 3.5 Flash compare to GPT-5.5 in benchmarks?

Gemini 3.5 Flash scores CharXiv-R: 84.2%, MCP Atlas: 83.6%, MMMU-Pro: 83.6%, OSWorld-Verified: 78.4%, Terminal-Bench 2.0: 76.2%. GPT-5.5 scores Tau2 Telecom: 98.0%, ARC-AGI: 95.0%, GPQA: 93.6%, ARC-AGI v2: 85.0%, GDPval-MM: 84.9%.

Is Gemini 3.5 Flash cheaper than GPT-5.5?

Gemini 3.5 Flash is 3.3x cheaper for input tokens. Gemini 3.5 Flash costs $1.50/M input and $9.00/M output via google. GPT-5.5 costs $5.00/M input and $30.00/M output via openai.

What are the context window sizes for Gemini 3.5 Flash and GPT-5.5?

Gemini 3.5 Flash supports 1.0M tokens and GPT-5.5 supports 1.1M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 3.5 Flash and GPT-5.5?

Key differences include context window (1.0M vs 1.1M), input pricing ($1.50 vs $5.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.5 Flash and GPT-5.5?

Gemini 3.5 Flash is developed by Google and GPT-5.5 is developed by OpenAI.

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