Models

gpt-5.5 vs grok-4.5

Output tokens cost $30.00 per million on gpt-5.5 and $6.00 per million on grok-4.5. Input tokens cost $5.00 per million on gpt-5.5 and $2.00 per million on grok-4.5. Cached input tokens are billed at $0.50 per million on gpt-5.5 and $0.50 per million on grok-4.5. Context windows are 1,050,000 tokens on gpt-5.5 and 1,000,000 tokens on grok-4.5. First-token latency measured on AIHubMix is 5.4s on gpt-5.5 and 1.8s on grok-4.5. Measured output throughput is 49.1 tokens/s on gpt-5.5 and 38.4 tokens/s on grok-4.5. On the LMArena coding leaderboard gpt-5.5 scores 1508 and grok-4.5 scores 1520.

OpenAIgpt-5.5Grokgrok-4.5
OpenAI
gpt-5.5
OpenAI · text, image → text

GPT-5.5 raises the baseline for complex production workflows. It’s a strong fit for coding use cases, tool-heavy agents, grounded assistants, long-context retrieval, product-spec-to-plan workflows, and customer-facing workflows where execution quality and response polish are critical.

Input$5.00 /M
Output$30.00 /M
Grok
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

Specs & Pricing

Prices are per million tokens. Latency and throughput are rolling averages measured on AIHubMix.

gpt-5.5
grok-4.5
Input price
$5.00
$2.00
Output price
$30.00
$6.00
Cache read
$0.50
$0.50
Context window
1,050,000
1,000,000
Max output
128,000
1,000,000
Latency (first token)
5.4 s
1.8 s
Throughput
49.1 TPS
38.4 TPS
Modalities
textimage
textimage
Features
thinkingfunction callingstructured outputswebtools
thinkingtoolsfunction callingstructured outputslong context
Endpoints
chat_completions · claude_api · responses

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

Usage on AIHubMix last 30 days

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

gpt-5.5grok-4.5

Tokens / day

-

Requests / day

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Live Performance last 3 days

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

gpt-5.5grok-4.5

Throughput (TPS)

-

Latency (s)

-

Uptime (%)

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Arena Scores

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

Text
gpt-5.5grok-4.5
1420146015001540
Overall
14691476
Coding
15081520
Math
14881499
Hard prompts
14911495
Instruction following
14631473
Multi-turn
14721480
Creative writing
14471448
Longer query
14821483
Chinese
15251530
English
14741480
Vision
gpt-5.5grok-4.5
126013001340
Overall
12821287
OCR
12951298
Diagram
13221326
Homework
13251329

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
gpt-5.5
$750 /mo

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

FAQ

Which is cheaper: gpt-5.5, grok-4.5?

grok-4.5: $6.00/M output tokens; gpt-5.5: $30.00/M. Use the cost calculator above to estimate your own workload.

How do their coding arena scores compare?

grok-4.5: 1520; gpt-5.5: 1508 (LMArena coding leaderboard).

Which responds faster?

grok-4.5: 1.8s first-token latency measured on AIHubMix; see the live performance charts above for how each model behaves across the day.

How large is each context window?

gpt-5.5 accepts 1,050,000 and grok-4.5 accepts 1,000,000 input tokens. Maximum output per request is 128,000 tokens on gpt-5.5 and 1,000,000 tokens on grok-4.5.

Which one generates tokens faster?

gpt-5.5 at 49.1 tokens/s and grok-4.5 at 38.4 tokens/s, measured as output throughput on AIHubMix — a separate metric from first-token latency.

What inputs and capabilities does each model support?

gpt-5.5 accepts text and image input and supports thinking, function calling, structured outputs, web search and tool calling; grok-4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context.

Can I call gpt-5.5 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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