Models

Gemini 3.5 Flash vs Grok 4.5

Output tokens cost $9.00 per million on Gemini 3.5 Flash and $6.00 per million on Grok 4.5. Input tokens cost $1.50 per million on Gemini 3.5 Flash and $2.00 per million on Grok 4.5. Cached input tokens are billed at $0.15 per million on Gemini 3.5 Flash and $0.50 per million on Grok 4.5. Context lengths are 1,000,000 tokens on Gemini 3.5 Flash and 500,000 tokens on Grok 4.5. Time to first token (TTFT) measured on AIHubMix is 4.0s on Gemini 3.5 Flash and 1.4s on Grok 4.5. Measured output throughput is 118.3 tok/s on Gemini 3.5 Flash and 27.7 tok/s on Grok 4.5. On the LMArena coding leaderboard Gemini 3.5 Flash scores 1507 and Grok 4.5 scores 1523.

GoogleGemini 3.5 FlashGrokGrok 4.5
Google logo
Gemini 3.5 Flash
Google · text, image, audio, video → text

Gemini 3.5 Flash provides sustained frontier-level intelligence optimized for real-world tasks at a higher speed and lower cost. Designed for the agentic era, it excels at sub-agent deployment, multi-step workflows, and long-horizon tasks at scale. This model is particularly effective for rapid agentic loops involving complex coding cycles and iterations.

Input$1.50 /M
Output$9.00 /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$2.00 /M
Output$6.00 /M

Pricing & Specifications

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

Gemini 3.5 Flash
Grok 4.5
Input /M
$1.50
$2.00
Output /M
$9.00
$6.00
Cache read /M
$0.15
$0.50
Context length
1,000,000
500,000
Max output
64,000
500,000
Time to First Token
4.0 s
1.4 s
Throughput
118.3 tok/s
27.7 tok/s
Modalities
textimageaudiovideo
textimage
Supported Parameters
thinkingtoolsfunction callingstructured outputswebdeepsearchlong context
thinkingtoolsfunction callingstructured outputslong context
API Formats
chat_completions · gemini_api · claude_api
Released
May 19, 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-3.5-flashgrok-4.5

Tokens / day

-

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-3.5-flashgrok-4.5

Throughput (tok/s)

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TTFT (s)

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Uptime (%)

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LMArena Benchmarks

LMArena ratings by capability (Bradley-Terry, commonly called Elo). Higher is better.

Text
gemini-3.5-flashgrok-4.5
1420146015001540
Overall
14701478
Coding
15071523
Math
14781503
Hard prompts
14951496
Instruction following
14661466
Multi-turn
14771485
Creative writing
14491466
Longer query
14821485
Chinese
15111527
English
14751476
Vision
gemini-3.5-flashgrok-4.5
126013001340
Overall
12821286
OCR
12941295
Diagram
13061321
Homework
12941328
WebDev Arena
gemini-3.5-flashgrok-4.5
1440150015601620
Overall
14991556
React
14921559
HTML
15191577
Gaming
15261586
Simulations
15171598
Data analytics
14701522

Source: LMArena (arena.ai) leaderboard, imported by AIHubMix. Models without published ratings are omitted per chart.

Cost calculator

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

Grok 4.5
$210 /mo
Gemini 3.5 Flash
$225 /mo

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

FAQ

Which is cheaper: Gemini 3.5 Flash, Grok 4.5?

Grok 4.5: $6.00/M output tokens; Gemini 3.5 Flash: $9.00/M. Use the cost calculator above to estimate your own workload.

How do their coding arena scores compare?

Grok 4.5: 1523; Gemini 3.5 Flash: 1507 (LMArena coding leaderboard).

Which responds faster?

Grok 4.5: 1.4s 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 3.5 Flash accepts 1,000,000 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 64,000 tokens on Gemini 3.5 Flash and 500,000 tokens on Grok 4.5.

Which one generates tokens faster?

Gemini 3.5 Flash at 118.3 tok/s and Grok 4.5 at 27.7 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 3.5 Flash accepts text, image, audio and video input and supports thinking, tool calling, function calling, structured outputs, web search, deep 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 3.5 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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