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Gemini 3.8 Flash vs Grok 4.3

Gemini 3.8 Flash leads the LLM Stats Score 50.5 to 22.3. Gemini 3.8 Flash is 1.0x cheaper per token.

Google · xAI · Updated for 2026

Which is better?

Gemini 3.8 Flash leads the overall LLM Stats Score 50.5 to 22.3, ranking #17 overall.

Gemini 3.8 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 3.8 Flash

  • overall performance matters — it scores 50.5 and ranks #17 on LLM Stats
  • your work emphasizes reasoning and agents — it leads those capability indexes
  • you process long inputs — it offers a 1,048,576 token context window
  • you want the most recent training data — it shipped Sep 2026

Choose Grok 4.3

  • you want predictable pricing at $1.25/M input and $2.50/M output

At a glance

The differences that matter most.

Gemini 3.8 Flash
Google
Grok 4.3
xAI
Core performance indexes
LLM Stats Score
50.5
#17
22.3
#177
Reasoning
46.9
#25
22.6
#169
Agents
35.6
#18
10.5
#115
Cost, coverage & limits
Benchmark wins
—
—
Input price
$0.75 / M
$1.25 / M
Output price
$3.75 / M
$2.50 / M
Context window
1,048,576
1,000,000

Individual benchmarks

13 reported for Gemini 3.8 Flash · 1 for Grok 4.3

No common benchmarks found

Gemini 3.8 Flash and Grok 4.3don't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.

Human preference

Blind head-to-head votes and playground preference scores

Pricing Analysis

Price comparison per million tokens

Gemini 3.8 Flash costs less

For input processing, Gemini 3.8 Flash ($0.75/1M tokens) is 1.7x cheaper than Grok 4.3 ($1.25/1M tokens).

For output processing, Gemini 3.8 Flash ($3.75/1M tokens) is 1.5x more expensive than Grok 4.3 ($2.50/1M tokens).

In conclusion, Grok 4.3 is more expensive than Gemini 3.8 Flash.*

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

Lowest available price from all providers
Mon Sep 21 2026 • llm-stats.com
Google
Gemini 3.8 Flash
Input tokens$0.75
Output tokens$3.75
Best providerGoogle
xAI
Grok 4.3
Input tokens$1.25
Output tokens$2.50
Best providerxAI
Notice missing or incorrect data?Start an Issue→

Context Window

Maximum input and output token capacity

Gemini 3.8 Flash accepts 1,048,576 input tokens compared to Grok 4.3's 1,000,000 tokens. Only Gemini 3.8 Flash specifies output context (65,536 tokens).

Google
Gemini 3.8 Flash
Input1,048,576 tokens
Output65,536 tokens
xAI
Grok 4.3
Input1,000,000 tokens
Output- tokens
Mon Sep 21 2026 • llm-stats.com

Input capabilities

Documented input modalities across available providers

Gemini 3.8 Flash supports multimodal inputs, whereas Grok 4.3 does not.

Gemini 3.8 Flash can handle both text and other forms of data like images, making it suitable for multimodal applications.

Gemini 3.8 Flash

Text
Images
Audio
Video

Grok 4.3

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 3.8 Flash

Proprietary

Closed source

Grok 4.3

Proprietary

Closed source

Release Timeline

When each model was launched

Gemini 3.8 Flash was released on 2026-09-02, while Grok 4.3 was released on 2026-05-06.

Gemini 3.8 Flash is 4 months newer than Grok 4.3.

Gemini 3.8 Flash

Sep 2, 2026

2 weeks ago

3mo newer
Grok 4.3

May 6, 2026

4 months ago

Knowledge Cutoff

When training data ends

Gemini 3.8 Flash has a documented knowledge cutoff of 2026-03-31, while Grok 4.3's cutoff date is not specified.

We can confirm Gemini 3.8 Flash's training data extends to 2026-03-31, but cannot make a direct comparison without Grok 4.3's cutoff date.

Gemini 3.8 Flash

Mar 2026

Grok 4.3

—

Provider Availability

Gemini 3.8 Flash is available from Google. Grok 4.3 is available from xAI.

Gemini 3.8 Flash

google logo
Google
Input Price:Input: $0.75/1MOutput Price:Output: $3.75/1M

Grok 4.3

xai logo
xAI
Input Price:Input: $1.25/1MOutput Price:Output: $2.50/1M
* 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 3.8 Flash and Grok 4.3 side-by-side, then vote on the output you prefer.

Gemini 3.8 Flash
✓ Preferred
Grok 4.3
Open in Playground

FAQ

Common questions about Gemini 3.8 Flash vs Grok 4.3.

Which is better, Gemini 3.8 Flash or Grok 4.3?

Gemini 3.8 Flash leads the LLM Stats Score 50.5 to 22.3. Gemini 3.8 Flash is made by Google and Grok 4.3 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 3.8 Flash compare to Grok 4.3 in benchmarks?

Gemini 3.8 Flash scores Terminal-Bench 2.1: 89.4%, LVBench: 87.1%, CharXiv-R: 86.2%, LABBench2: 86.2%, DeepSWE 1.1: 73.7%. Grok 4.3 scores Finance Agent v2: 37.7%.

Is Gemini 3.8 Flash cheaper than Grok 4.3?

Gemini 3.8 Flash is 1.7x cheaper for input tokens. Gemini 3.8 Flash costs $0.75/M input and $3.75/M output via google. Grok 4.3 costs $1.25/M input and $2.50/M output via xai.

What are the context window sizes for Gemini 3.8 Flash and Grok 4.3?

Gemini 3.8 Flash supports 1.0M tokens and Grok 4.3 supports 1.0M tokens. A larger context window lets you process longer documents, conversations, or codebases in a single request.

What are the main differences between Gemini 3.8 Flash and Grok 4.3?

Key differences include LLM Stats Score (50.5 vs 22.3), context window (1.0M vs 1.0M), input pricing ($0.75 vs $1.25/M), multimodal support (yes vs no). See the full comparison above for benchmark-by-benchmark results.

Who makes Gemini 3.8 Flash and Grok 4.3?

Gemini 3.8 Flash is developed by Google and Grok 4.3 is developed by xAI.

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