Model Comparison

Gemini 3.5 Flash-Lite vs o1-proWhich is better in 2026?

Comparing Gemini 3.5 Flash-Lite and o1-pro across benchmarks, pricing, and capabilities.

Verdict: Gemini 3.5 Flash-Lite vs o1-pro — which is better?

Gemini 3.5 Flash-Lite (by Google) and o1-pro (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.

Choose Gemini 3.5 Flash-Lite if…

  • you want the most recent training data — it shipped Jul 2026

Choose o1-pro if…

  • you are already invested in the OpenAI ecosystem

Performance Benchmarks

Comparative analysis across standard metrics

No common benchmarks found

Gemini 3.5 Flash-Lite and o1-prodon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Arena Performance

Human preference votes

Context Window

Maximum input and output token capacity

Only Gemini 3.5 Flash-Lite specifies input context (1,048,576 tokens). Only Gemini 3.5 Flash-Lite specifies output context (65,536 tokens).

Google
Gemini 3.5 Flash-Lite
Input1,048,576 tokens
Output65,536 tokens
OpenAI
o1-pro
Input- tokens
Output- tokens
Tue Jul 21 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.5 Flash-Lite and o1-pro support multimodal inputs.

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

Gemini 3.5 Flash-Lite

Text
Images
Audio
Video

o1-pro

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-Lite

Proprietary

Closed source

o1-pro

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.5 Flash-Lite was released on 2026-07-21, while o1-pro was released on 2024-12-17.

Gemini 3.5 Flash-Lite is 19 months newer than o1-pro.

Gemini 3.5 Flash-Lite

Jul 21, 2026

0 days ago

1.6yr newer
o1-pro

Dec 17, 2024

1.6 years ago

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash-Lite has a knowledge cutoff of 2026-03-31, while o1-pro has a cutoff of 2023-09-30.

Gemini 3.5 Flash-Lite has more recent training data (up to 2026-03-31), making it potentially better informed about events through that date compared to o1-pro (2023-09-30).

Gemini 3.5 Flash-Lite

Mar 2026

2.5 yr newer
o1-pro

Sep 2023

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Larger context window (1,048,576 tokens)
OpenAI

No standout differentiators in the data we have for this pair.

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemini 3.5 Flash-Lite and o1-pro side-by-side, then vote on the output you prefer.

Gemini 3.5 Flash-Lite
✓ Preferred
o1-pro
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.5 Flash-Lite
OpenAI
o1-pro

FAQ

Common questions about Gemini 3.5 Flash-Lite vs o1-pro.

Which is better, Gemini 3.5 Flash-Lite or o1-pro?

Gemini 3.5 Flash-Lite (Google) and o1-pro (OpenAI) each have strengths in different areas. Compare their benchmark scores, pricing, context windows, and capabilities above to determine which fits your needs.

How does Gemini 3.5 Flash-Lite compare to o1-pro in benchmarks?

Gemini 3.5 Flash-Lite scores CharXiv-R: 76.5%, OSWorld-Verified: 74.0%, SWE-Bench Pro: 54.2%, Terminal-Bench 2.1: 54.0%, MLE-Bench: 39.2%. o1-pro scores AIME 2024: 86.0%, GPQA: 79.0%.

What are the context window sizes for Gemini 3.5 Flash-Lite and o1-pro?

Gemini 3.5 Flash-Lite supports 1.0M tokens and o1-pro supports an unknown number of tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

Who makes Gemini 3.5 Flash-Lite and o1-pro?

Gemini 3.5 Flash-Lite is developed by Google and o1-pro is developed by OpenAI.

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