The "Updates 1-11" likely refer to the initial weekly batches of the Mega Update Service 2025 , which provides approximately 5,000 new games per week Overview of Mega Database 2025 Total Content
This collection includes the roughly 55,000 new games (approx. 5,000 per week) played globally in early 2025. "Both Formats": This indicates the file contains the database in both the classic .cbh format (compatible with ChessBase 16 and older) and the format introduced with ChessBase 17 .7z Extension: Chess Megabase 2025 Updates 1 11 -both Formats- 7z
After extracting the 7z, immediately create a backup of the CBH files on an external SSD. Re-downloading 5.2 GB is painful; having a local copy of Updates 1 through 11 will save you when Update 12 drops in December. The "Updates 1-11" likely refer to the initial
Chess Megabase 2025 Updates 1 11, both formats, 7z, CBH vs PGN, ChessBase 17 installation, November 2025 chess database. Re-downloading 5
format usually refers to third-party compressed archives containing: CBV (ChessBase Archive Format)
Be cautious of “free” 7z archives from torrent sites – many contain outdated or corrupted data. The 2025 update cycle is actively checked by ChessBase’s digital signature.
These updates represent the first 11 weeks of 2025, ensuring your reference database reflects the most recent professional tournament play.