Model Comparison

Gemini 3.1 Flash-Lite vs Grok 4.5Which is better in 2026?

Grok 4.5 significantly outperforms across most benchmarks. Gemini 3.1 Flash-Lite is 5.3x cheaper per token.

Verdict: Gemini 3.1 Flash-Lite vs Grok 4.5 — which is better?

Gemini 3.1 Flash-Lite (by Google) and Grok 4.5 (by xAI) 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 3.1 Flash-Lite outperforms in 0 benchmarks, while Grok 4.5 is better at 1 benchmark (GPQA). Grok 4.5 significantly outperforms across most benchmarks.

On price, Gemini 3.1 Flash-Lite is roughly 5.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 3.1 Flash-Lite also accepts a larger context window (1,000,000 input tokens), making it the stronger choice for long documents and large codebases.

Choose Gemini 3.1 Flash-Lite if…

  • cost matters — it's about 5.3x cheaper per token
  • you process long inputs — it offers a 1,000,000 token context window

Choose Grok 4.5 if…

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

Performance Benchmarks

Comparative analysis across standard metrics

1 benchmarks

Gemini 3.1 Flash-Lite outperforms in 0 benchmarks, while Grok 4.5 is better at 1 benchmark (GPQA).

Grok 4.5 significantly outperforms across most benchmarks.

Mon Jul 20 2026 • llm-stats.com

Arena Performance

Human preference votes

Pricing Analysis

Price comparison per million tokens

Gemini 3.1 Flash-Lite costs less

For input processing, Gemini 3.1 Flash-Lite ($0.25/1M tokens) is 8.0x cheaper than Grok 4.5 ($2.00/1M tokens).

For output processing, Gemini 3.1 Flash-Lite ($1.50/1M tokens) is 4.0x cheaper than Grok 4.5 ($6.00/1M tokens).

In conclusion, Grok 4.5 is more expensive than Gemini 3.1 Flash-Lite.*

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

Lowest available price from all providers
Mon Jul 20 2026 • llm-stats.com
Google
Gemini 3.1 Flash-Lite
Input tokens$0.25
Output tokens$1.50
Best providerGoogle
xAI
Grok 4.5
Input tokens$2.00
Output tokens$6.00
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.1 Flash-Lite accepts 1,000,000 input tokens compared to Grok 4.5's 500,000 tokens. Only Gemini 3.1 Flash-Lite specifies output context (65,536 tokens).

Google
Gemini 3.1 Flash-Lite
Input1,000,000 tokens
Output65,536 tokens
xAI
Grok 4.5
Input500,000 tokens
Output- tokens
Mon Jul 20 2026 • llm-stats.com

Input Capabilities

Supported data types and modalities

Both Gemini 3.1 Flash-Lite and Grok 4.5 support multimodal inputs.

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

Gemini 3.1 Flash-Lite

Text
Images
Audio
Video

Grok 4.5

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 3.1 Flash-Lite

Proprietary

Closed source

Grok 4.5

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.1 Flash-Lite was released on 2026-03-03, while Grok 4.5 was released on 2026-07-16.

Grok 4.5 is 5 months newer than Gemini 3.1 Flash-Lite.

Gemini 3.1 Flash-Lite

Mar 3, 2026

4 months ago

Grok 4.5

Jul 16, 2026

4 days ago

4mo newer

Knowledge Cutoff

When training data ends

Gemini 3.1 Flash-Lite has a knowledge cutoff of 2025-01-31, while Grok 4.5 has a cutoff of 2026-02-01.

Grok 4.5 has more recent training data (up to 2026-02-01), making it potentially better informed about events through that date compared to Gemini 3.1 Flash-Lite (2025-01-31).

Gemini 3.1 Flash-Lite

Jan 2025

Grok 4.5

Feb 2026

1.1 yr newer

Provider Availability

Gemini 3.1 Flash-Lite is available from Google. Grok 4.5 is available from xAI.

Gemini 3.1 Flash-Lite

google logo
Google
Input Price:Input: $0.25/1MOutput Price:Output: $1.50/1M

Grok 4.5

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $6.00/1M
* 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
xAI
Higher GPQA score (93.0% vs 86.9%)

Detailed Comparison

Interactive Arena

Judge for yourself.

Run your own prompts against Gemini 3.1 Flash-Lite and Grok 4.5 side-by-side, then vote on the output you prefer.

Gemini 3.1 Flash-Lite
✓ Preferred
Grok 4.5
Open in Playground
AI Model Comparison Table
Feature
Google
Gemini 3.1 Flash-Lite
xAI
Grok 4.5

FAQ

Common questions about Gemini 3.1 Flash-Lite vs Grok 4.5.

Which is better, Gemini 3.1 Flash-Lite or Grok 4.5?

Grok 4.5 significantly outperforms across most benchmarks. Gemini 3.1 Flash-Lite is made by Google and Grok 4.5 is made by xAI. The best choice depends on your use case — compare their benchmark scores, pricing, and capabilities above.

How does Gemini 3.1 Flash-Lite compare to Grok 4.5 in benchmarks?

Gemini 3.1 Flash-Lite scores MMMLU: 88.9%, GPQA: 86.9%, VideoMMMU: 84.8%, MMMU-Pro: 76.8%, CharXiv-R: 73.2%. Grok 4.5 scores GPQA: 93.0%, Terminal-Bench 2.1: 83.3%, Artificial Analysis Coding Agent Index v1.1: 76.0%, SWE-Bench Pro: 64.7%, AA-Omniscience Index: 63.0%.

Is Gemini 3.1 Flash-Lite cheaper than Grok 4.5?

Gemini 3.1 Flash-Lite is 8.0x cheaper for input tokens. Gemini 3.1 Flash-Lite costs $0.25/M input and $1.50/M output via google. Grok 4.5 costs $2.00/M input and $6.00/M output via xai.

What are the context window sizes for Gemini 3.1 Flash-Lite and Grok 4.5?

Gemini 3.1 Flash-Lite supports 1.0M tokens and Grok 4.5 supports 500K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 3.1 Flash-Lite and Grok 4.5?

Key differences include context window (1.0M vs 500K), input pricing ($0.25 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.1 Flash-Lite and Grok 4.5?

Gemini 3.1 Flash-Lite is developed by Google and Grok 4.5 is developed by xAI.

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