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Gemini 1.5 Flash vs Grok-2

Grok-2 leads the LLM Stats Score 11.5 to 6.1. Gemini 1.5 Flash is 15.2x cheaper per token.

Google · xAI · Updated for 2026

Which is better?

Grok-2 leads the overall LLM Stats Score 11.5 to 6.1, ranking #247 overall.

In the 7 individual benchmarks reported for both models, Grok-2 wins 6; this is a narrower head-to-head signal than the composite indexes.

On price, Gemini 1.5 Flash is roughly 15.2x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.

Gemini 1.5 Flash also accepts a larger context window (1,048,576 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 1.5 Flash

  • cost matters — it's about 15.2x cheaper per token
  • you process long inputs — it offers a 1,048,576 token context window

Choose Grok-2

  • overall performance matters — it scores 11.5 and ranks #247 on LLM Stats
  • your work emphasizes reasoning — it leads those capability indexes
  • you value its reported benchmark strengths — it wins 6 of 7 exact shared results
  • you want the most recent training data — it shipped Aug 2024

At a glance

The differences that matter most.

Core performance indexes
6.1
#282
11.5
#247
5.8
#280
11.5
#243
-0.3
#234
9.3
#168
Cost, coverage & limits
Benchmark wins
1 of 7
6 of 7
Input price
$0.15 / M
$2.00 / M
Output price
$0.60 / M
$10.00 / M
Context window
1,048,576
128,000

Capability indexes

Additional strengths measured across groups of related public benchmarks

5 shared
Index
Gemini 1.5 Flash
Grok-2
10.9#240
18.4#170
5.9#147
8.0#134
9.5#117
11.4#109
6.0#157
18.8#89
6.0#144
18.8#76
Conservative TrueSkill rating · higher is betterHow scores work

Individual benchmarks

22 reported for Gemini 1.5 Flash · 8 for Grok-2

7 shared

Gemini 1.5 Flash outperforms in 1 benchmarks (MATH), while Grok-2 is better at 6 benchmarks (GPQA, HumanEval, MathVista, MMLU, MMLU-Pro, MMMU).

Grok-2 significantly outperforms across most benchmarks.

Mon Sep 07 2026 • llm-stats.com

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Gemini 1.5 Flash costs less

For input processing, Gemini 1.5 Flash ($0.15/1M tokens) is 13.3x cheaper than Grok-2 ($2.00/1M tokens).

For output processing, Gemini 1.5 Flash ($0.60/1M tokens) is 16.7x cheaper than Grok-2 ($10.00/1M tokens).

In conclusion, Grok-2 is more expensive than Gemini 1.5 Flash.*

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

Lowest available price from all providers
Mon Sep 07 2026 • llm-stats.com
Google
Gemini 1.5 Flash
Input tokens$0.15
Output tokens$0.60
Best providerGoogle
xAI
Grok-2
Input tokens$2.00
Output tokens$10.00
Best providerxAI
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Context Window

Maximum input and output token capacity

Gemini 1.5 Flash accepts 1,048,576 input tokens compared to Grok-2's 128,000 tokens. Gemini 1.5 Flash can generate longer responses up to 8,192 tokens, while Grok-2 is limited to 8,000 tokens.

Google
Gemini 1.5 Flash
Input1,048,576 tokens
Output8,192 tokens
xAI
Grok-2
Input128,000 tokens
Output8,000 tokens
Mon Sep 07 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Both Gemini 1.5 Flash and Grok-2 support multimodal inputs.

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

Gemini 1.5 Flash

Text
Images
Audio
Video

Grok-2

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 1.5 Flash

Proprietary

Closed source

Grok-2

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 1.5 Flash was released on 2024-05-01, while Grok-2 was released on 2024-08-13.

Grok-2 is 3 months newer than Gemini 1.5 Flash.

Gemini 1.5 Flash

May 1, 2024

2.4 years ago

Grok-2

Aug 13, 2024

2.1 years ago

3mo newer

Knowledge Cutoff

When training data ends

Gemini 1.5 Flash has a documented knowledge cutoff of 2023-11-01, while Grok-2's cutoff date is not specified.

We can confirm Gemini 1.5 Flash's training data extends to 2023-11-01, but cannot make a direct comparison without Grok-2's cutoff date.

Gemini 1.5 Flash

Nov 2023

Grok-2

Provider Availability

Gemini 1.5 Flash is available from Google. Grok-2 is available from xAI.

Gemini 1.5 Flash

google logo
Google
Input Price:Input: $0.15/1MOutput Price:Output: $0.60/1M

Grok-2

xai logo
xAI
Input Price:Input: $2.00/1MOutput Price:Output: $10.00/1M
* Prices shown are per million tokens

Outputs Comparison

Notice missing or incorrect data?Start an Issue discussion

Judge for yourself.

Run your own prompts against Gemini 1.5 Flash and Grok-2 side-by-side, then vote on the output you prefer.

Gemini 1.5 Flash
✓ Preferred
Grok-2
Open in Playground

FAQ

Common questions about Gemini 1.5 Flash vs Grok-2.

Which is better, Gemini 1.5 Flash or Grok-2?

Grok-2 leads the LLM Stats Score 11.5 to 6.1. Gemini 1.5 Flash is made by Google and Grok-2 is made by xAI. The best choice depends on your use case — compare their capability indexes, individual benchmarks, pricing, and limits above.

How does Gemini 1.5 Flash compare to Grok-2 in benchmarks?

Gemini 1.5 Flash scores XSTest: 97.0%, FLEURS: 90.4%, HellaSwag: 86.5%, GSM8k: 86.2%, BIG-Bench Hard: 85.5%. Grok-2 scores DocVQA: 93.6%, HumanEval: 88.4%, MMLU: 87.5%, MATH: 76.1%, MMLU-Pro: 75.5%.

Is Gemini 1.5 Flash cheaper than Grok-2?

Gemini 1.5 Flash is 13.3x cheaper for input tokens. Gemini 1.5 Flash costs $0.15/M input and $0.60/M output via google. Grok-2 costs $2.00/M input and $10.00/M output via xai.

What are the context window sizes for Gemini 1.5 Flash and Grok-2?

Gemini 1.5 Flash supports 1.0M tokens and Grok-2 supports 128K tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 1.5 Flash and Grok-2?

Key differences include LLM Stats Score (6.1 vs 11.5), context window (1.0M vs 128K), input pricing ($0.15 vs $2.00/M). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 1.5 Flash and Grok-2?

Gemini 1.5 Flash is developed by Google and Grok-2 is developed by xAI.