Gemini 3 Flash Preview or Grok 4.7: which to choose?

Side-by-side comparison

Criterion	Gemini 3 Flash Preview	Grok 4.7
Developer	Google DeepMind	xAI
Released	December 17, 2025	September 21, 2026
Capability index	80.3 / 100	79.9 / 100
Input price	$0.50	$2
Output price	$3	$6
Cost of a typical task	$0.016	$0.052
Context window	1,048,576 tokens	500,000 tokens
Maximum output	65,536 tokens	500,000 tokens
Reasoning mode	Yes	Yes
Tool calling	Yes	Yes
Accepted inputs	text, image, video, audio, PDF	text, image, PDF
Open weights	No	No
Knowledge cutoff	January 2025	May 2026

The match-up at a glance

This comparison pits two mid-range models, balancing quality and cost against each other: Gemini 3 Flash Preview and Grok 4.7, one from Google DeepMind, the other from xAI. The first dates from December 17, 2025, the second from September 21, 2026.

All figures below come from public sources checked on October 22, 2026: models.dev and OpenRouter for prices and capabilities, Epoch AI for scores.

Which one is more capable?

On our capability index, Gemini 3 Flash Preview scores 80.3 out of 100 and Grok 4.7 79.9. The gap is too small to separate them.

On the 3 benchmarks reported for both, Gemini 3 Flash Preview wins 0 times and Grok 4.7 3:

GPQA Diamond (PhD-level science questions): Gemini 3 Flash Preview 89.4%, Grok 4.7 92.7%
OTIS Mock AIME (competition mathematics problems): Gemini 3 Flash Preview 95.6%, Grok 4.7 98.1%
FrontierMath (very hard research-level mathematics): Gemini 3 Flash Preview 51.2%, Grok 4.7 53%

Budget

Gemini 3 Flash Preview costs $0.50 per million input tokens and $3 per million output tokens; Grok 4.7 costs $2 and $6.

For a typical agent task (read 20,000 tokens, write 2,000), expect $0.016 with Gemini 3 Flash Preview versus $0.052 with Grok 4.7. Gemini 3 Flash Preview is 3.3 times cheaper, a gap that adds up quickly over 1,000 tasks: $36 difference.

Run the numbers with your own volumes in the agent cost calculator.

Context and capabilities

Gemini 3 Flash Preview reads more in one go: 1,048,576 tokens of context (roughly 1,573 pages), versus 500,000 for Grok 4.7.

Reasoning mode: Gemini 3 Flash Preview yes, Grok 4.7 yes. Tool calling: Gemini 3 Flash Preview yes, Grok 4.7 yes. Image input: Gemini 3 Flash Preview yes, Grok 4.7 yes.

Neither publishes its weights: both are used through an API.

Knowledge cutoff: January 2025 for Gemini 3 Flash Preview, May 2026 for Grok 4.7.

In short

Our reading of the data:

Choose Gemini 3 Flash Preview for a lower cost and a larger context window.
Choose Grok 4.7 for a more recent release.

This verdict relies on public figures; it does not replace a trial on your own tasks.

Frequently asked questions

Gemini 3 Flash Preview or Grok 4.7: which is better?

On our index (Epoch AI data), Gemini 3 Flash Preview scores 80.3 and Grok 4.7 79.9 out of 100. The best choice also depends on price and on your use case.

Which one is cheaper?

Gemini 3 Flash Preview. To read 20,000 tokens and write 2,000, expect $0.016 with Gemini 3 Flash Preview and $0.052 with Grok 4.7 (prices as of October 22, 2026).

Which one has the larger context window?

Gemini 3 Flash Preview, with 1,048,576 tokens versus 500,000.

Can I run Gemini 3 Flash Preview or Grok 4.7 on my own servers?

No: both are closed models, available through an API.