Models

GPT 5 Nano vs Grok 4.5

Compare GPT 5 Nano from OpenAI 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.

OpenAIGPT 5 NanoGrokGrok 4.5
OpenAI logo
GPT 5 Nano
OpenAI · text, image → text

GPT-5-Nano is the smallest and fastest variant in the GPT-5 system, designed specifically for developer tools and environments that demand rapid interactions and ultra-low latency. While it offers a more lightweight solution with limited reasoning depth compared to its larger counterparts, GPT-5-Nano excels in core capabilities such as instruction-following and maintaining critical safety features. As the successor to GPT-4.1-nano, it provides an optimal choice for cost-sensitive or real-time applications, where efficiency and speed are paramount. Particularly well-suited for summarization and classification tasks, GPT-5-Nano is a powerful tool for developers needing a swift, reliable AI model for streamlined processes.

Input$0.05 /M
Output$0.40 /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.

GPT 5 Nano
Grok 4.5
Input /M
$0.05
$2.00
Output /M
$0.40
$6.00
Cache read /M
$0.01
$0.50
Context length
400,000
500,000
Max output
128,000
500,000
Time to First Token
5.1 s
1.7 s
Throughput
94.4 tok/s
30.7 tok/s
Modalities
textimage
textimage
Supported Parameters
thinkingtoolsfunction callingstructured outputs
thinkingtoolsfunction callingstructured outputslong context
API Formats
Released
-
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.

gpt-5-nanogrok-4.5

Tokens / day

-

Requests / day

-

Performance Past 3 Days

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

gpt-5-nanogrok-4.5

Throughput (tok/s)

-

TTFT (s)

-

Uptime (%)

-

LMArena Benchmarks

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

Text
gpt-5-nanogrok-4.5
12201300138014601540
Overall
13371470
Coding
13821523
Math
13451478
Hard prompts
13541495
Instruction following
13261466
Multi-turn
13231477
Creative writing
12481449
Longer query
13291485
Chinese
13781511
English
13441475
Vision
gpt-5-nanogrok-4.5
11201180124013001360
Overall
11471282
OCR
11561295
Diagram
11541321
Homework
11811328

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.

GPT 5 Nano
$9.00 /mo
Grok 4.5
$210 /mo

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

FAQ

Which is cheaper: GPT 5 Nano, Grok 4.5?

GPT 5 Nano: $0.40/M output tokens; Grok 4.5: $6.00/M. Use the cost calculator above to estimate your own workload.

How do their coding arena scores compare?

Grok 4.5: 1523; GPT 5 Nano: 1382 (LMArena coding leaderboard).

Which responds faster?

Grok 4.5: 1.7s 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?

GPT 5 Nano accepts 400,000 and Grok 4.5 accepts 500,000 input tokens. Maximum output per request is 128,000 tokens on GPT 5 Nano and 500,000 tokens on Grok 4.5.

Which one generates tokens faster?

GPT 5 Nano at 94.4 tok/s and Grok 4.5 at 30.7 tok/s, measured as output throughput on AIHubMix — a separate metric from time to first token.

What inputs and capabilities does each model support?

GPT 5 Nano accepts text and image input and supports thinking, tool calling, function calling and structured outputs; 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 Nano 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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