Models

Gemini 3.8 Flash vs Grok 4.5

Compare Gemini 3.8 Flash from Google and Grok 4.5 from Grok on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the AIHubMix API.

GoogleGemini 3.8 FlashGrokGrok 4.5
Google logo
Gemini 3.8 Flash
Google · text, image, audio, video → text

Gemini 3.8 Flash is Google's most intelligent Flash-series model, designed for long-running software engineering tasks, autonomous agents, and complex enterprise workflows, while retaining the Flash series' fast responsiveness and cost-effectiveness.

Input$0.75 /M
Output$3.75 /M
Cache read$0.075 /M
Grok logo
Grok 4.5
Grok · text, image → text

Grok 4.5 was trained on datasets spanning knowledge in coding, science, engineering, and math. With both intelligent and efficient reasoning, Grok 4.5 excels at real engineering tasks and exceeds comparable leading models at these tasks.

Input$2 /M
Output$6 /M
Cache read$0.5 /M

Pricing & Specifications

Prices are per million tokens. Time to First Token and throughput are rolling averages measured on AIHubMix.

Gemini 3.8 Flash
Grok 4.5
Input /M
$0.75
$2
Output /M
$3.75
$6
Cache read /M
$0.075
$0.5
Context length
1,048,576
500,000
Max output
65,536
500,000
Time to First Token
2.1 s
2.7 s
Throughput
243.1 tok/s
27.1 tok/s
Modalities
textimageaudiovideo
textimage
Supported Parameters
thinkingtoolsfunction callingstructured outputsweblong context
thinkingtoolsfunction callingstructured outputslong context
API Formats
chat_completions · gemini_api · claude_api
Released
September 2, 2026
July 2026

Promotional prices show the discounted rate; see each model page for promotion windows.

Activity Past 30 Days

Daily traffic served through AIHubMix — how demand for each model is trending.

gemini-3.8-flashgrok-4.5

Tokens / day

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Requests / day

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Performance Past 3 Days

Measured on real AIHubMix traffic, hourly buckets. Gaps mean no traffic in that hour.

gemini-3.8-flashgrok-4.5

Throughput (tok/s)

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TTFT (s)

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Uptime (%)

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Cost calculator

Estimate your monthly bill for the same workload on each model.

Gemini 3.8 Flash
$101 /mo
Grok 4.5
$210 /mo

Monthly = daily × 30. Discounted rates applied where a promotion is active.

FAQ

Which is cheaper: Gemini 3.8 Flash, Grok 4.5?

Gemini 3.8 Flash: $3.75/M output tokens; Grok 4.5: $6/M. Use the cost calculator above to estimate your own workload.

Which responds faster?

Gemini 3.8 Flash: 2.1s time to first token measured on AIHubMix; see the live performance charts above for how each model behaves across the day.

How large is each context window?

Gemini 3.8 Flash accepts 1,048,576 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 65,536 tokens on Gemini 3.8 Flash and 500,000 tokens on Grok 4.5.

Which one generates tokens faster?

Gemini 3.8 Flash at 243.1 tok/s and Grok 4.5 at 27.1 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.

What inputs and capabilities does each model support?

Gemini 3.8 Flash accepts text, image, audio and video input and supports thinking, tool calling, function calling, structured outputs, web search and long context; Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context.

Can I call Gemini 3.8 Flash and Grok 4.5 with the same API key?

Yes. AIHubMix serves every model on this page behind one OpenAI-compatible endpoint, so switching between them is a one-line change to the model field — no second account, key or SDK.

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