Model Comparison

Gemini 3.5 Flash-Lite vs GPT-5 CodexWhich is better in 2026?

Comparing Gemini 3.5 Flash-Lite and GPT-5 Codex across benchmarks, pricing, and capabilities.

Verdict: Gemini 3.5 Flash-Lite vs GPT-5 Codex — which is better?

Gemini 3.5 Flash-Lite (by Google) and GPT-5 Codex (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 GPT-5 Codex 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 GPT-5 Codexdon'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
GPT-5 Codex
Input- tokens
Output- tokens
Sun Jul 26 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Gemini 3.5 Flash-Lite supports multimodal inputs, whereas GPT-5 Codex does not.

Gemini 3.5 Flash-Lite can handle both text and other forms of data like images, making it suitable for multimodal applications.

Gemini 3.5 Flash-Lite

Text
Images
Audio
Video

GPT-5 Codex

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

GPT-5 Codex

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.5 Flash-Lite was released on 2026-07-21, while GPT-5 Codex was released on 2025-09-15.

Gemini 3.5 Flash-Lite is 10 months newer than GPT-5 Codex.

Gemini 3.5 Flash-Lite

Jul 21, 2026

4 days ago

10mo newer
GPT-5 Codex

Sep 15, 2025

10 months ago

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash-Lite has a knowledge cutoff of 2026-03-31, while GPT-5 Codex has a cutoff of 2024-09-30.

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 GPT-5 Codex (2024-09-30).

Gemini 3.5 Flash-Lite

Mar 2026

1.5 yr newer
GPT-5 Codex

Sep 2024

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Larger context window (1,048,576 tokens)
Supports multimodal inputs
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 GPT-5 Codex side-by-side, then vote on the output you prefer.

Gemini 3.5 Flash-Lite
✓ Preferred
GPT-5 Codex
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.5 Flash-Lite
OpenAI
GPT-5 Codex

FAQ

Common questions about Gemini 3.5 Flash-Lite vs GPT-5 Codex.

Which is better, Gemini 3.5 Flash-Lite or GPT-5 Codex?

Gemini 3.5 Flash-Lite (Google) and GPT-5 Codex (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 GPT-5 Codex 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%. GPT-5 Codex scores SWE-Bench Verified: 74.5%.

What are the context window sizes for Gemini 3.5 Flash-Lite and GPT-5 Codex?

Gemini 3.5 Flash-Lite supports 1.0M tokens and GPT-5 Codex supports an unknown number of 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-Lite and GPT-5 Codex?

Key differences include multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.5 Flash-Lite and GPT-5 Codex?

Gemini 3.5 Flash-Lite is developed by Google and GPT-5 Codex is developed by OpenAI.

Related comparisons