Breaking

xAI Opens Grok 4.5 in Private Beta Inside SpaceX and Tesla

July 6, 2026 at 13:07 EDT

Foundation Models
AI Agents
Software Dev & Coding

xAI has begun offering "Grok 4.5," powered by a roughly 1.5-trillion-parameter foundation model, as a private beta for internal use at SpaceX and Tesla. A public API and general release remain undated, and no independent third-party verification has yet taken place.

June 28, 2026 · xAI

Grok 4.5 Enters Private Beta — Built on a 1.5-Trillion-Parameter Core

xAI's next model runs on a new "V9" foundation, supplemented with coding data from Cursor. Access is limited to internal teams at SpaceX and Tesla, with early evaluations said to approach Anthropic's Claude Opus.

~1.5T

Parameters in the new "V9" foundation model

Monthly

Cadence of newly trained-from-scratch models in 2026

Firms with access: SpaceX & Tesla only

Grok 4.3 (public) vs Grok 4.5 (private beta)

Grok 4.5 context, pricing and benchmarks remain unannounced.

Context Window

1,000,000

Grok 4.3 tokens

N/A

Grok 4.5

API Price (per 1M tokens)

$1.25

4.3 input

$2.50

4.3 output

The Cursor Data Flywheel

V9 foundation model (~1.5T)

→

+ Cursor coding data

→

RL & "Grok Build" daily gains

→

Internal stress test at SpaceX/Tesla

The Optimistic Read

Early internal evals reportedly approach or exceed Claude Opus. Feature flags for Grok 4.5/5.0 spotted on grok.com fuel expectations of a broad release within weeks.

The Skeptical Read

Claims rest on self-evaluation and unverified benchmarks. The public target slipped from late May by ~a month, and no independent numbers exist yet.

What's next — The larger Grok 5 (~6T parameters, Mixture-of-Experts) is still in training. Grok 4.3 remains the public flagship until a wider Grok 4.5 rollout and independent benchmarks put its real standing to the test.

Continue reading

The rest of this article is for AI News Blitz readers. Choose an option below to keep reading.