Model

Grok 4.3

CLOSED

SpaceXAI · Grok 4.3 family · released Apr 30, 2026

Default/low reasoning-effort configuration of xAI's (now SpaceXAI's) April 2026 flagship. 1M-token context, native video input, always-on reasoning defaulting to the cheapest 'low' effort tier. Predecessor to Grok 4.5; xAI did not publish a full first-party benchmark table alongside launch.

ReasoningCodingVisionFunction callingTool useAgentic

1973.3

Elo · unrated

Parameters

Undisclosed

Active params

Undisclosed

Context

1M tokens

Architecture

Mixture-of-Experts (size undisclosed); always-on reasoning with configurable effort (none/low/medium/high, default low)

License

Proprietary

Languages

—

API price (in/out)

$1.25 / $2.5

Modalities

text · vision · video

Benchmark results

Bar shows position within the tracked field; marker = field best

Agents' Last ExamAgents20.1%#18

best: GPT-5.6 · 52.7%

Run it locally

Closed weights — available via API only. No local deployment.

Input / M tok

$1.25

Output / M tok

$2.5

Grok 4.3 family

Elo progression across releases

Grok 4.3Apr 20261973.3 Grok 4.3 (High)Apr 20262298.5

Resources

DOCShttps://docs.x.ai APIAvailable via SpaceXAI API

API price $1.25/$2.5 · each benchmark row carries its own source badge (see methodology)