PrimeWire

This might help for some.- Earth 828
Earth-828 is an alternate universe in the Marvel Cinematic Universe (MCU) that is home to the Fantastic Four.
The designation Earth-828 was revealed by director Matt Shakman and is a tribute to Jack Kirby, the co-creator of the Fantastic Four, whose birthday is on August 28.

The Fantastic Four: First Steps, which was released on July 25, 2025, is set on Earth-828.
This setting allows the film to introduce the team in their own world without conflicting with the main MCU timeline, Earth-616.
Director Matt Shakman explained that placing the Fantastic Four on Earth-828 avoids continuity issues, as their presence in the main MCU timeline would raise questions about their absence during major events like the Snap and the Battle of New York.

Earth-828 is distinct from other MCU universes such as Earth-616 and Earth-838, and it is designed to bridge the visual and thematic space between these realities, facilitating potential crossovers in future films like Avengers: Doomsday and Secret Wars.
The film’s ending shows the Fantastic Four preparing to relocate Earth-828 to a distant solar system to protect it from Galactus, although the full relocation does not occur on screen.The choice of Earth-828 as the setting for the Fantastic Four’s MCU debut was also influenced by Kevin Feige, who emphasized that the film is a “no-homework-required movie,” making it accessible to new viewers.