Grok 4.3

Grok 4.3 is positioned as a frontier-tier model aimed at enterprise agent development, with particular emphasis on tool-driven customer support and complex document understanding. Its design centers on a configurable reasoning system that lets developers tune the depth of inference—from a fast, near-instant setting for simple requests through graduated low, medium, and high effort modes for harder problems. This makes the model adaptable to a wide range of deployment scenarios, from lightweight chat interactions to long-running, multi-step agent tasks that demand careful deliberation.

In benchmark evaluations, Grok 4.3 has claimed top rankings on the Artificial Analysis Omniscience benchmark, the Tau2 Telecom tool-calling benchmark, and Vals AI's Case Law and Corporate Finance tests, highlighting strengths in factual reliability, real-world agent behavior, and complex document analysis. The model is reported to deliver strong intelligence-per-dollar efficiency relative to other frontier options, and it sustains a very long context window that enables reasoning across extensive codebases, legal documents, and multi-turn agent conversations. These traits make it a practical fit for organizations building production-grade assistants, research copilots, and domain-specific agents where both reasoning quality and throughput matter.

OpenRouterx-ai/grok-4.3grok

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Quick Info

Provider: OpenRouter
Model key: x-ai/grok-4.3
Release date: Apr 17, 2026
Last updated: Apr 17, 2026
Input modalities
Output modalities
Capabilities

Cost

Input token cost: $1.25
Output token cost: $2.50

Limits

Output tokens: 900,000 tokens
Context window: 1,000,000 tokens

Transparent token rates

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Rates are shown per one million tokens. Combined means one million input plus one million output tokens.

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Latest news about Grok 4.3

OpenRouter

Official sourceDocumentation

The xAI developer documentation explicitly names grok-4.3 as the redirect and billing target for eight retired model slugs effective May 15, 2026, including grok-3, grok-4-0709, grok-4-fast-reasoning and its non-reasoning sibling, grok-4-1-fast-reasoning and its non-reasoning sibling, grok-code-fast-1, and grok-imagine The page also pins grok-4.3 API pricing at $1.25 per 1M input tokens and $2.50 per 1M output tokens, and lists recommended explicit replacements per workload. A successor slug, grok-build-0.1, is named as the redirect target for grok-code-fast-1 specifically. The migration is now retrospective relative to the May 15, 2

OpenRouter

CoverageBenchmark

The TechJack Solutions breakdown confirms grok-4.3 as a predecessor xAI model released in April 2026, which was subsequently superseded by Grok 4.5 (released July 8-9, 2026) as the vendor's frontier model. The piece independently corroborates the grok-4.3 release window and lineage position within the Grok 4 family, pr However, the article's primary technical details (context window, pricing, benchmarks) concern Grok 4.5 rather than grok-4.3, so grok-4.3-specific facts are limited to the release date and lineage context. The source is a third-party editorial breakdown rather than official documentation, and includes marketing-style f

OpenRouter

Official sourceBenchmark

Benchmark scores and performance metrics for xAI: Grok 4.3 - Grok 4.3 is a reasoning model from xAI. It accepts text and image inputs with text output, and is suited for agentic workflows, instruction-following tasks, and applications requiring high factual accuracy. Reasoning is always active and cannot be disabled or