Grok 4.3
Grok 4.3 is xAI's always-on reasoning model for accuracy-critical work — advanced logic, math, science, and multi-step investigations. Access it through Velokey's unified endpoint with below-list pricing.
Use cases
Scientific analysis & research · Advanced logic & math
Input
Text, image
Output
Text
Billing
Per token
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Sign up to get $0.5 in free credits — about 20 free images
Pricing details
Transparent usage-based pricing with no hidden fees.
Detailed Pricing
Usage-based pricing breakdown
| Spec | Price | Official | Savings |
|---|---|---|---|
| Input/1M tokens | 1 Credits≈$1 | 1.25 Credits | -20% |
| Output/1M tokens | 2 Credits≈$2 | 2.5 Credits | -20% |
| Cache Read/1M tokens | 0.16 Credits≈$0.16 | 0.2 Credits | -20% |
Billing Rules
- Output price varies by model, resolution, quality, duration, or token usage.
- Uploaded reference files may be charged separately when supported.
- Add-on capabilities such as web search or image search may be billed per request.
- Token-based models are billed by input and output tokens.
- If the primary route is unavailable, Velokey may automatically switch to a stable fallback route when possible.
- Usage is pay-as-you-go with transparent credit deduction.
* Final cost depends on the generated result.
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Affordable Grok 4.3 API
Access xAI's Grok 4.3 on Velokey — always-on reasoning, accuracy-critical problem solving, a 1M-token context, and vision, files, and web search for agents, with a unified endpoint and below-list pricing for production apps.
Meet Grok 4.3 and its API access
Grok 4.3 is xAI's reasoning model, released on April 30, 2026, and designed for complex, accuracy-critical tasks — advanced logic, math, scientific analysis, and multi-step investigations — on an improved architecture over Grok 4.20. Reasoning is a permanent, always-on state: it thinks before every response, and the reasoning_effort parameter tunes how deeply it thinks, defaulting to low. It ships with a 1,000,000-token context window, a December 2025 knowledge cutoff, and support for tool use, vision input, file input, and web search. xAI launched it at an aggressively low price and introduced a fast voice-cloning suite alongside it. Velokey provides an affordable, easy-to-integrate Grok 4.3 API: a unified chat endpoint, a clear request flow, and below-list pricing for production systems, agent pipelines, and automation tools.
Always-on reasoning
Reasoning is a permanent state — Grok 4.3 thinks before every response. The reasoning_effort parameter controls thinking depth and defaults to low, so you dial depth up only for the hardest problems.
View Documentation →
Accuracy-critical problem solving
Built for advanced logic, math, and scientific analysis on an improved architecture over Grok 4.20 — fit for multi-step investigations where correctness matters most.
View Documentation →
1M-token context with tools
A 1,000,000-token context window plus vision input, file input, tool use, and web search lets it reason over long material and combine that with live external context for agents.
View Documentation →
Efficient and affordable
A low default reasoning_effort keeps everyday calls light, and Grok 4.3 launched at an aggressively low price — deep results without heavy cost.
View Documentation →
How to deploy the Grok 4.3 API on Velokey
Get started with just a few steps.
Sign up and get an API Key
Sign in to the Velokey console to generate an API Key that authenticates every request sent to Grok 4.3.
Configure request parameters
Set model to grok-4-3 and submit messages. Reasoning is always on; set reasoning_effort (defaults to low) to tune thinking depth, and attach tools, vision, files, or web search.
Integrate and start calling
Send requests to Velokey's unified /v1/chat/completions endpoint to power assistants, agents, and automation, with usage managed in one console.
Real-world use cases for Grok 4.3
From research to engineering, covering many accuracy-critical and agentic scenarios.
Scientific analysis & research
Advanced reasoning for scientific analysis and multi-step investigations where accuracy is critical.
Advanced logic & math
Always-on reasoning with tunable depth — fit for hard logic, proofs, and quantitative problems.
Agentic systems
Tool use, vision, file input, and web search combine reasoning with external context for autonomous agents.
Long-document reasoning
A 1M-token context lets it reason across long reports, papers, and codebases in a single request.
Vision & file understanding
Vision and file input let it analyze images, diagrams, and documents alongside its reasoning.
Complex data investigations
Multi-step reasoning over gathered context — fit for data analysis and structured investigations.
Why choose Velokey for Grok 4.3
Discount on list price
Call Grok 4.3 at a lower price on Velokey — pay-as-you-go with no forced subscription, reducing upfront cost.
Unified API interface
One API Key accesses Grok 4.3 and other models — no juggling multiple accounts and keys, simplifying integration.
Complete docs and integration guidance
Endpoint references, parameter details including reasoning_effort, and examples help you adopt reasoning, long context, and tools smoothly.
Stable and highly available
Automatic failover and stable fallback routes maintain availability when the primary route is down, keeping production reliable.
API Reference
Complete API call examples and parameter descriptions
Endpoint
https://api.velokey.ai/v1/chat/completionsAuthentication
Bearer YOUR_API_KEYRequest Example
curl https://api.velokey.ai/v1/chat/completions \
-X POST \
-H "Authorization: Bearer YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "grok-4.3",
"messages": [{"role": "user", "content": "Hello!"}],
"temperature": 0.7
}'Response Example
{
"id": "req_abc123",
"model": "grok-4.3",
"created": 1234567890,
"data": { ... }
}Grok 4.3 API FAQ
What is Grok 4.3 best at?
It's xAI's reasoning model built for complex, accuracy-critical tasks: advanced logic, math, scientific analysis, and multi-step investigations, on an improved architecture over Grok 4.20.
How does its reasoning work?
Reasoning is a permanent, always-on state — Grok 4.3 thinks before every response. The reasoning_effort parameter controls how deeply it thinks and defaults to low, so you can raise it for the hardest problems.
What is the context window?
Grok 4.3 has a 1,000,000-token context window and a knowledge cutoff of December 2025, so it can reason over very long material.
What tools and inputs are supported?
It supports tool use, vision input, file input, and web search, making it well suited to agentic systems that combine reasoning with external context.
How is it billed on Velokey?
Grok 4.3 launched at an aggressively low price. This page's pricing area shows the current Velokey price, billed by input and output tokens with a discount on list price.
Start building with Grok 4.3 today
Use one API key to access low-cost, stable AI models through Velokey.