Models

Grok 4.5 vs O3

Output tokens cost $6.00 per million on Grok 4.5 and $8.00 per million on O3. Input tokens cost $2.00 per million on Grok 4.5 and $2.00 per million on O3. Cached input tokens are billed at $0.50 per million on Grok 4.5 and $0.50 per million on O3. Context lengths are 500,000 tokens on Grok 4.5 and 200,000 tokens on O3. Time to first token (TTFT) measured on AIHubMix is 1.6s on Grok 4.5 and 6.5s on O3. Measured output throughput is 25.2 tok/s on Grok 4.5 and 40.3 tok/s on O3. On the LMArena coding leaderboard Grok 4.5 scores 1523 and O3 scores 1459.

GrokGrok 4.5OpenAIO3
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
OpenAI logo
O3
OpenAI · text, image → text

OpenAI o3 is a powerful model across multiple domains, setting a new standard for coding, math, science, and visual reasoning tasks.

Input$2.00 /M
Output$8.00 /M

Pricing & Specifications

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

Grok 4.5
O3
Input /M
$2.00
$2.00
Output /M
$6.00
$8.00
Cache read /M
$0.50
$0.50
Context length
500,000
200,000
Max output
500,000
100,000
Time to First Token
1.6 s
6.5 s
Throughput
25.2 tok/s
40.3 tok/s
Modalities
textimage
textimage
Supported Parameters
thinkingtoolsfunction callingstructured outputslong context
thinkingtoolsfunction callingstructured outputs
API Formats
Released
July 2026
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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.

grok-4.5o3

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.

grok-4.5o3

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
grok-4.5o3
1360142014801540
Overall
14311470
Coding
14591523
Math
14471478
Hard prompts
14401495
Instruction following
14021466
Multi-turn
14181477
Creative writing
13831449
Longer query
14081485
Chinese
14641511
English
14381475
Vision
grok-4.5o3
12001240128013201360
Overall
12171282
OCR
12221295
Diagram
12301321
Homework
12471328

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
O3
$240 /mo

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

FAQ

Which is cheaper: Grok 4.5, O3?

Grok 4.5: $6.00/M output tokens; O3: $8.00/M. Use the cost calculator above to estimate your own workload.

How do their coding arena scores compare?

Grok 4.5: 1523; O3: 1459 (LMArena coding leaderboard).

Which responds faster?

Grok 4.5: 1.6s 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?

Grok 4.5 accepts 500,000 and O3 accepts 200,000 input tokens. Maximum output per request is 500,000 tokens on Grok 4.5 and 100,000 tokens on O3.

Which one generates tokens faster?

O3 at 40.3 tok/s and Grok 4.5 at 25.2 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.

What inputs and capabilities does each model support?

Grok 4.5 accepts text and image input and supports thinking, tool calling, function calling, structured outputs and long context; O3 accepts text and image input and supports thinking, tool calling, function calling and structured outputs.

Can I call Grok 4.5 and O3 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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