Model Comparison

Gemini 3 Flash vs GPT-5.2 CodexWhich is better in 2026?

GPT-5.2 Codex significantly outperforms across most benchmarks. Gemini 3 Flash is 4.3x cheaper per token.

Verdict: Gemini 3 Flash vs GPT-5.2 Codex — which is better?

Gemini 3 Flash (by Google) and GPT-5.2 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.

Gemini 3 Flash outperforms in 0 benchmarks, while GPT-5.2 Codex is better at 1 benchmark (Terminal-Bench 2.0). GPT-5.2 Codex significantly outperforms across most benchmarks.

On price, Gemini 3 Flash is roughly 4.3x 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.

Choose Gemini 3 Flash if…

  • cost matters — it's about 4.3x cheaper per token
  • you process long inputs — it offers a 1,000,000 token context window

Choose GPT-5.2 Codex if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks
  • you want the most recent training data — it shipped Jan 2026
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Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Gemini 3 Flash outperforms in 0 benchmarks, while GPT-5.2 Codex is better at 1 benchmark (Terminal-Bench 2.0).

GPT-5.2 Codex significantly outperforms across most benchmarks.

Sat Jun 13 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3 Flash costs less

For input processing, Gemini 3 Flash ($0.50/1M tokens) is 3.5x cheaper than GPT-5.2 Codex ($1.75/1M tokens).

For output processing, Gemini 3 Flash ($3.00/1M tokens) is 4.7x cheaper than GPT-5.2 Codex ($14.00/1M tokens).

In conclusion, GPT-5.2 Codex 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 13 2026 • llm-stats.com
Google
Gemini 3 Flash
Input tokens$0.50
Output tokens$3.00
Best providerGoogle
OpenAI
GPT-5.2 Codex
Input tokens$1.75
Output tokens$14.00
Best providerOpenAI
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 GPT-5.2 Codex's 400,000 tokens. GPT-5.2 Codex can generate longer responses up to 128,000 tokens, while Gemini 3 Flash is limited to 65,536 tokens.

Google
Gemini 3 Flash
Input1,000,000 tokens
Output65,536 tokens
OpenAI
GPT-5.2 Codex
Input400,000 tokens
Output128,000 tokens
Sat Jun 13 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3 Flash and GPT-5.2 Codex support multimodal inputs.

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

Gemini 3 Flash

Text
Images
Audio
Video

GPT-5.2 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 Flash

Proprietary

Closed source

GPT-5.2 Codex

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3 Flash was released on 2025-12-17, while GPT-5.2 Codex was released on 2026-01-14.

GPT-5.2 Codex is 1 month newer than Gemini 3 Flash.

Gemini 3 Flash

Dec 17, 2025

5 months ago

GPT-5.2 Codex

Jan 14, 2026

5 months ago

4w newer

Knowledge Cutoff

When training data ends

Gemini 3 Flash has a documented knowledge cutoff of 2025-01-31, while GPT-5.2 Codex'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 GPT-5.2 Codex's cutoff date.

Gemini 3 Flash

Jan 2025

GPT-5.2 Codex

—

Provider Availability

Gemini 3 Flash is available from Google. GPT-5.2 Codex is available from OpenAI.

Gemini 3 Flash

google logo
Google
Input Price:Input: $0.50/1MOutput Price:Output: $3.00/1M

GPT-5.2 Codex

openai logo
OpenAI
Input Price:Input: $1.75/1MOutput Price:Output: $14.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Larger context window (1,000,000 tokens)
Less expensive input tokens
Less expensive output tokens
OpenAI
Higher Terminal-Bench 2.0 score (64.0% vs 47.6%)

Detailed Comparison

AI Model Comparison Table
Feature
Google
Gemini 3 Flash
OpenAI
GPT-5.2 Codex

FAQ

Common questions about Gemini 3 Flash vs GPT-5.2 Codex.

Which is better, Gemini 3 Flash or GPT-5.2 Codex?

GPT-5.2 Codex significantly outperforms across most benchmarks. Gemini 3 Flash is made by Google and GPT-5.2 Codex is made by OpenAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemini 3 Flash compare to GPT-5.2 Codex in benchmarks?

Gemini 3 Flash scores Vending-Bench 2: 100.0%, AIME 2025: 99.7%, Global PIQA: 92.8%, MMMLU: 91.8%, GPQA: 90.4%. GPT-5.2 Codex scores Terminal-Bench 2.0: 64.0%, SWE-Bench Pro: 56.4%.

Is Gemini 3 Flash cheaper than GPT-5.2 Codex?

Gemini 3 Flash is 3.5x cheaper for input tokens. Gemini 3 Flash costs $0.50/M input and $3.00/M output via google. GPT-5.2 Codex costs $1.75/M input and $14.00/M output via openai.

What are the context window sizes for Gemini 3 Flash and GPT-5.2 Codex?

Gemini 3 Flash supports 1.0M tokens and GPT-5.2 Codex supports 400K 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 Flash and GPT-5.2 Codex?

Key differences include context window (1.0M vs 400K), input pricing ($0.50 vs $1.75/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3 Flash and GPT-5.2 Codex?

Gemini 3 Flash is developed by Google and GPT-5.2 Codex is developed by OpenAI.

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