Model Comparison

Gemini 3.5 Flash-Lite vs o3Which is better in 2026?

o3 significantly outperforms across most benchmarks. Gemini 3.5 Flash-Lite is 4.1x cheaper per token.

Verdict: Gemini 3.5 Flash-Lite vs o3 — which is better?

Gemini 3.5 Flash-Lite (by Google) and o3 (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-Lite outperforms in 0 benchmarks, while o3 is better at 1 benchmark (CharXiv-R). o3 significantly outperforms across most benchmarks.

On price, Gemini 3.5 Flash-Lite is roughly 4.1x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.5 Flash-Lite also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.

Choose Gemini 3.5 Flash-Lite if…

  • cost matters — it's about 4.1x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Jul 2026

Choose o3 if…

  • you want the strongest raw capability — it leads on 1 of 1 shared benchmarks

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Gemini 3.5 Flash-Lite outperforms in 0 benchmarks, while o3 is better at 1 benchmark (CharXiv-R).

o3 significantly outperforms across most benchmarks.

Thu Jul 23 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3.5 Flash-Lite costs less

For input processing, Gemini 3.5 Flash-Lite ($0.30/1M tokens) is 6.7x cheaper than o3 ($2.00/1M tokens).

For output processing, Gemini 3.5 Flash-Lite ($2.50/1M tokens) is 3.2x cheaper than o3 ($8.00/1M tokens).

In conclusion, o3 is more expensive than Gemini 3.5 Flash-Lite.*

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

Lowest available price from all providers
Thu Jul 23 2026 • llm-stats.com
Google
Gemini 3.5 Flash-Lite
Input tokens$0.30
Output tokens$2.50
Best providerGoogle
OpenAI
o3
Input tokens$2.00
Output tokens$8.00
Best providerOpenAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.5 Flash-Lite accepts 1,048,576 input tokens compared to o3's 200,000 tokens. o3 can generate longer responses up to 100,000 tokens, while Gemini 3.5 Flash-Lite is limited to 65,536 tokens.

Google
Gemini 3.5 Flash-Lite
Input1,048,576 tokens
Output65,536 tokens
OpenAI
o3
Input200,000 tokens
Output100,000 tokens
Thu Jul 23 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.5 Flash-Lite and o3 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

o3

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

o3

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.5 Flash-Lite was released on 2026-07-21, while o3 was released on 2025-04-16.

Gemini 3.5 Flash-Lite is 15 months newer than o3.

Gemini 3.5 Flash-Lite

Jul 21, 2026

2 days ago

1.3yr newer
o3

Apr 16, 2025

1.3 years ago

Knowledge Cutoff

When training data ends

Gemini 3.5 Flash-Lite has a knowledge cutoff of 2026-03-31, while o3 has a cutoff of 2024-05-31.

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 o3 (2024-05-31).

Gemini 3.5 Flash-Lite

Mar 2026

1.8 yr newer
o3

May 2024

Provider Availability

Gemini 3.5 Flash-Lite is available from Google. o3 is available from OpenAI.

Gemini 3.5 Flash-Lite

google logo
Google
Input Price:Input: $0.30/1MOutput Price:Output: $2.50/1M

o3

openai logo
OpenAI
Input Price:Input: $2.00/1MOutput Price:Output: $8.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion→

Key Takeaways

Google
Larger context window (1,048,576 tokens)
Less expensive input tokens
Less expensive output tokens
OpenAI
Higher CharXiv-R score (78.6% vs 76.5%)
GoogleGemini 3.5 Flash-Lite
OpenAIo3
Compare in Playground

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemini 3.5 Flash-Lite and o3 side-by-side, then vote on the output you prefer.

Gemini 3.5 Flash-Lite
✓ Preferred
o3
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.5 Flash-Lite
OpenAI
o3

FAQ

Common questions about Gemini 3.5 Flash-Lite vs o3.

Which is better, Gemini 3.5 Flash-Lite or o3?

o3 significantly outperforms across most benchmarks. Gemini 3.5 Flash-Lite is made by Google and o3 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-Lite compare to o3 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%. o3 scores COLLIE: 98.4%, AIME 2024: 91.6%, ARC-AGI: 88.0%, MathVista: 86.8%, AIME 2025: 86.4%.

Is Gemini 3.5 Flash-Lite cheaper than o3?

Gemini 3.5 Flash-Lite is 6.7x cheaper for input tokens. Gemini 3.5 Flash-Lite costs $0.30/M input and $2.50/M output via google. o3 costs $2.00/M input and $8.00/M output via openai.

What are the context window sizes for Gemini 3.5 Flash-Lite and o3?

Gemini 3.5 Flash-Lite supports 1.0M tokens and o3 supports 200K 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 o3?

Key differences include context window (1.0M vs 200K), input pricing ($0.30 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.5 Flash-Lite and o3?

Gemini 3.5 Flash-Lite is developed by Google and o3 is developed by OpenAI.

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