Gemini 3.8 Flash High vs Grok 4.7 Xhigh compared

This comparison puts Google's Gemini 3.8 Flash (High) next to SpaceXAI's Grok 4.7 (Xhigh). Throughput is the standout difference: 121 tokens per second for Gemini 3.8 Flash High against 65 tokens per second for Grok 4.7 Xhigh. What follows is built entirely from tracked data, so where the catalogue is silent, this page says so instead of guessing.

Waiting time

Measured output speed is 121 tokens per second for Gemini 3.8 Flash High and 65 tokens per second for Grok 4.7 Xhigh. That makes Gemini 3.8 Flash High roughly 1.9 times as fast at writing. The wait for the first token averages 27 seconds on Gemini 3.8 Flash High against 43 seconds on Grok 4.7 Xhigh. Gemini 3.8 Flash High gets to its first token 1.6 times as fast. Waits that long are felt on every chat-style request, though they matter less for batch jobs.

Put together, a 400-token answer would take about 31 seconds from Gemini 3.8 Flash High and 49 seconds from Grok 4.7 Xhigh, counting the first-token wait.

What they cost

The list prices are $0.75 in and $3.75 out for Gemini 3.8 Flash High, and $2.00 in and $6.00 out for Grok 4.7 Xhigh, per million tokens. Grok 4.7 Xhigh costs 1.6 times as much per output token.

A reference job of 1 million input tokens and 200,000 output tokens costs $1.50 with Gemini 3.8 Flash High and $3.20 with Grok 4.7 Xhigh, so Gemini 3.8 Flash High saves $1.70. Scale it up to extracting fields from 20,000 pages of 1,500 tokens into 150-token records and the bill is $33.75 for Gemini 3.8 Flash High against $78.00 for Grok 4.7 Xhigh. On a 3:1 blend of input to output tokens, that works out to $1.50 versus $3.00 per million.

Release timing

Gemini 3.8 Flash High came first, on September 2, 2026; Grok 4.7 Xhigh followed on September 21, 2026. That is close enough to count them as the same generation.

Reasoning and overall scores

The catalogue puts Gemini 3.8 Flash High at 30.8 and Grok 4.7 Xhigh at 35.5 on its intelligence index. A lead of this size is hard to dismiss as noise. In relative terms, Grok 4.7 Xhigh scores 15% higher.

For context, that places Gemini 3.8 Flash High 50th and Grok 4.7 Xhigh 38th out of 109 scored models still on offer.

Neither model has a separate coding or math index recorded yet, so those narrower comparisons will have to wait for more data.

Cost per point of intelligence

Dividing the blended price by the intelligence index gives a rough cost per point: $0.049 for Gemini 3.8 Flash High and $0.085 for Grok 4.7 Xhigh, per million tokens. Grok 4.7 Xhigh costs 1.7 times as much per point, which is the price of its lead.