Musk: Grok 4.4 Doubles to 1T Parameter, 4.5 Further Expands to 1.5T, Aiming for May Release

According to Watchtower Beating monitoring, xAI and Tesla CEO Musk responded on April 19th in X to a post in Tech Dev Notes, revealing Grok's two upcoming versions. The account had previously posted that the knowledge cutoff date for Grok 4.3 was December 2025. Musk's reply had three points: Grok 4.3 has received additional training; Grok 4.4's parameter size has doubled to 1T, with training data now covering up to early April 2026, expected to be released in early May; Grok 4.5 will further expand to 1.5T parameters, aiming for delivery by the end of May.

This set of figures completes what was unclear yesterday. Musk had also said on April 18 that the "true 1T flagship is about 5 days away from initial training completion" without specifying the model; today, it is clear that this refers to Grok 4.4, while 4.5 will be the next version of the 1.5T model.