Gemini 2.5 Flash-Lite vs Grok 4 Fast
Grok 4 Fast leads the LLM Stats Score 31.7 to 10.4. Gemini 2.5 Flash-Lite is 1.6x cheaper per token.
Google · xAI · Updated for 2026
Which is better?
Grok 4 Fast leads the overall LLM Stats Score 31.7 to 10.4, ranking #109 overall.
In the 5 individual benchmarks reported for both models, Grok 4 Fast wins 5; this is a narrower head-to-head signal than the composite indexes.
On price, Gemini 2.5 Flash-Lite is roughly 1.6x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Grok 4 Fast also accepts a larger context window (2,000,000 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Gemini 2.5 Flash-Lite
- cost matters — it's about 1.6x cheaper per token
- you need open weights you can self-host or fine-tune
Choose Grok 4 Fast
- overall performance matters — it scores 31.7 and ranks #109 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- you value its reported benchmark strengths — it wins 5 of 5 exact shared results
- you process long inputs — it offers a 2,000,000 token context window
- you want the most recent training data — it shipped Aug 2025
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
13 reported for Gemini 2.5 Flash-Lite · 7 for Grok 4 Fast
Gemini 2.5 Flash-Lite outperforms in 0 benchmarks, while Grok 4 Fast is better at 5 benchmarks (AIME 2025, GPQA, Humanity's Last Exam, LiveCodeBench, SimpleQA).
Grok 4 Fast significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 2.5 Flash-Lite ($0.10/1M tokens) is 2.0x cheaper than Grok 4 Fast ($0.20/1M tokens).
For output processing, Gemini 2.5 Flash-Lite ($0.40/1M tokens) is 1.3x cheaper than Grok 4 Fast ($0.50/1M tokens).
In conclusion, Grok 4 Fast is more expensive than Gemini 2.5 Flash-Lite.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Grok 4 Fast accepts 2,000,000 input tokens compared to Gemini 2.5 Flash-Lite's 1,048,576 tokens. Gemini 2.5 Flash-Lite can generate longer responses up to 65,536 tokens, while Grok 4 Fast is limited to 30,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Gemini 2.5 Flash-Lite and Grok 4 Fast support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 2.5 Flash-Lite
Grok 4 Fast
License
Usage and distribution terms
Gemini 2.5 Flash-Lite is licensed under Creative Commons Attribution 4.0 License, while Grok 4 Fast uses a proprietary license.
License differences may affect how you can use these models in commercial or open-source projects.
Creative Commons Attribution 4.0 License
Open weights
Proprietary
Closed source
Release Timeline
When each model was launched
Gemini 2.5 Flash-Lite was released on 2025-06-17, while Grok 4 Fast was released on 2025-08-28.
Grok 4 Fast is 2 months newer than Gemini 2.5 Flash-Lite.
Jun 17, 2025
1.2 years ago
Aug 28, 2025
1.0 years ago
2mo newerKnowledge Cutoff
When training data ends
Gemini 2.5 Flash-Lite has a documented knowledge cutoff of 2025-01-01, while Grok 4 Fast's cutoff date is not specified.
We can confirm Gemini 2.5 Flash-Lite's training data extends to 2025-01-01, but cannot make a direct comparison without Grok 4 Fast's cutoff date.
Jan 2025
—
Provider Availability
Gemini 2.5 Flash-Lite is available from Google. Grok 4 Fast is available from xAI.
Gemini 2.5 Flash-Lite
Grok 4 Fast
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 2.5 Flash-Lite and Grok 4 Fast side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 2.5 Flash-Lite vs Grok 4 Fast.