grok-4.5
The Grok 4.5 API gives developers access to xAI's frontier reasoning model, built for agentic software engineering, multi-step tool calling, and long-context code work. On GPTProto the grok 4.5 API runs 40% off — $1.2/1M input and $3.6/1M output tokens — behind a single OpenAI-compatible endpoint.

$ 1.2
$ 2

text

$ 3.6
$ 6

text

Related Models
All Models
Claude
Claude
claude-opus-5
$ 20
$ 25
Google
Google
gemini-3.6-flash
$ 4.5
$ 7.5
MoonshotAI
MoonshotAI
kimi-k3
$ 13.5
$ 15
OpenAI
OpenAI
gpt-5.6-luna
$ 0.96
$ 1.2
MiniMax
MiniMax
MiniMax-M3
$ 0.96
$ 1.2
Z-AI
Z-AI
glm-5.2
$ 3.96
$ 4.4

Grok 4.5 API

Core features of xAI's Grok 4.5 API on GPTProto — high-throughput serving, native reasoning control, and affordable, pay-as-you-go pricing.

High-Throughput Serving

The Grok 4.5 API streams 80–93 tokens per second, keeping agents and coding tools responsive at real-time speed even under sustained load.

AI Throughput

Reasoning Control

A native reasoning_effort parameter lets you scale Grok 4.5's reasoning depth per request — light for fast replies, high for complex agentic and coding tasks.

Logic Control

Affordable Pricing

Affordable grok 4.5 API pricing: $1.2/1M input and $3.6/1M output tokens — a standing 40% off, with pay-as-you-go billing and no monthly minimum.

API Cost

Built for Engineering

A frontier reasoning model tuned for STEM, engineering datasets, and technical workflows, with strong tool-calling accuracy and long-context code understanding through the Grok 4.5 API.

Grok-4.5 V9

What Is the Grok 4.5 API?

The Grok 4.5 API is xAI's frontier reasoning model served as a hosted endpoint, so you can send prompts and receive completions without running any infrastructure of your own. On GPTProto it sits behind an OpenAI-compatible interface: point your existing openai SDK at our base URL, drop in a grok 4.5 API key, and the model is live in your stack in minutes.

Grok 4.5 is tuned for agentic software engineering — multi-step tool calling, code generation, and long-context reasoning across large repositories. It takes text input and returns text output, and exposes a native reasoning_effort parameter so you can trade latency for deeper reasoning on the hardest tasks.

Why developers choose the Grok 4.5 API on GPTProto:

  • Affordable pricing — $1.2/1M input and $3.6/1M output tokens, a standing 40% off the standard rate, billed per token with no monthly minimum.
  • One key, every model — the same grok 4.5 API key also calls grok-4.3, grok-code-fast-1, and 100+ other models, so you can benchmark or fall back without opening new accounts.
  • No waitlist — sign up, top up, and get grok 4.5 API access the same day.

Grok 4.5 vs grok 4.3: 4.5 raises tool-calling accuracy and reasoning depth for technical workflows, while grok 4.3 stays a cheaper pick for lighter chat and drafting.

How to Get a grok-4.5 API Key

Getting a grok-4.5 API key takes four steps and a few minutes. Create a free GPTProto account, add credits, generate your key, and make your first call — at $1.2 / $3.6 it's a cheaper grok-4.5 API key than going direct, and one key works across every model on the platform. Full grok-4.5 Documentation is in the docs.

Sign up

Sign up

Create your free GPT Proto account to begin. You can set up an organization for your team at any time.

Top up

Top up

Your balance can be used across all models on the platform, including grok-4.5, giving you the flexibility to experiment and scale as needed.

Generate your API key

Generate your API key

In your dashboard, create an API key — you'll need it to authenticate when making requests to grok-4.5.

Make your first API call

Make your first API call

Use your API key with our sample code to send a request to grok-4.5 via GPT Proto and see instant AI-powered results.

Get API Key

Grok-4.5 Frequently Asked Questions

Common technical questions regarding Grok-4.5 integration and performance.

How does Grok-4.5 handle agentic software tasks?

Grok 4.5 is built for agentic workflows: it plans multi-step tasks, calls tools/functions in sequence, and reasons over long code contexts. Via the Grok 4.5 API on GPTProto it integrates with agent frameworks through a standard OpenAI-compatible schema.

What is the context window for Grok-4.5?

Currently, Grok-4.5 supports a 500,000-token context window. This ensures stability for long-form reasoning. For tasks requiring a full 1M-token window, we recommend using the Grok-4.3 model via our unified API.

How efficient is Grok-4.5 compared to other models?

On the Grok 4.5 API you pay $1.2/1M input and $3.6/1M output — 40% off — while getting 80–93 tokens/sec throughput, making it a cost-efficient frontier option versus the big-three models.

Does Grok-4.5 support native function calling?

Yes. The Grok 4.5 API supports native function/tool calling, so you can register functions and let the model choose when to invoke them — the core primitive for agentic and coding tools.

Can I use Grok-4.5 for real-time applications?

Yes. With 80–93 tokens/sec streaming and a low reasoning_effort setting, the grok 4.5 API is responsive enough for interactive chat, coding assistants, and real-time agents.

How do I control the model's reasoning depth?

Set the native reasoning_effort parameter on each grok 4.5 API request: lower values cut latency and cost for simple queries; higher values give deeper reasoning for hard engineering tasks.

Is the Grok 4.5 API open source?

Grok 4.5 is a proprietary xAI model, not open source. You access it as a managed grok 4.5 API — no weights to host — with GPTProto handling billing and OpenAI-compatible routing.

More GPTProto AI Tools

AI French Kissing Generator

Upload a photo of two people and turn it into a short, romantic kiss video. Our AI French kissing generator animates a natural lean-in and a gentle kiss in seconds — no editing skills needed.

Motion Control AI

Preserve character consistency and human-like movement across every frame with advanced motion control technology.

Retouch Photo Online

Retouch Photo Online

Restore old photos, eliminate background clutter, and conceal skin defects instantly using our advanced retouch AI.

Create Your AI Influencer

Create Your AI Influencer

Upload one reference photo and generate a consistent, photoreal virtual influencer you can place in any scene, outfit, or brand campaign — image-first, powered by 200+ models on a single balance.

Related Articles

More Blogs
How to Generate Video With an AI API: Seedance 2.0, ViduQ3, and 3 More Through One Key

How to Generate Video With an AI API: Seedance 2.0, ViduQ3, and 3 More Through One Key

Step-by-step: generate video with an AI API in ~10 lines of Python. One key reaches Seedance 2.0, ViduQ3, Kling, Hailuo & Veo — runnable code, real pricing.

GLM-5.2 vs DeepSeek V4 Pro: Benchmarks, Pricing, and Which One to Actually Use (2026)

GLM-5.2 vs DeepSeek V4 Pro: Benchmarks, Pricing, and Which One to Actually Use (2026)

GLM-5.2 vs DeepSeek V4 Pro: independent benchmarks (51 vs 44), real July 2026 pricing after DeepSeek's 75% cut, and which model fits your workload.

MiniMax M3 for Coding: Benchmarks, Real Pricing, and How to Call It via API (2026)

MiniMax M3 for Coding: Benchmarks, Real Pricing, and How to Call It via API (2026)

Is MiniMax M3 good for coding? Independent benchmarks vs vendor claims, the real API cost with its 512K price cliff explained, and runnable GPTProto code.

Best Claude Alternatives in 2026: Cheaper API Access, Honestly Compared

Best Claude Alternatives in 2026: Cheaper API Access, Honestly Compared

Claude alternatives compared for developers: run the same Opus 4.8 and Sonnet 5 for ~20% less, or switch to DeepSeek, GLM, and Grok. 2026 API prices inside.