Chess databases are a great tool for learning chess. You can review and play through historic games. You can also analyze large groups of games for common openings, endgames, etc.

There are a variety of chess databases out there, some free and some for sale. For example, you can buy the Chessbase Big Database which has over 8 million games. Or you can buy the Chessbase Mega Database which has the same number of games, but 85,000 of them are annotated. There are also websites where you can search through chess databases like

I wanted a copy of a large chess database that I could use to look through for opening reports, searching through historic games, etc.

For my purposes, I did not want to spend more money on a database at this time. I may change my mind in the future, in which case I’ll buy one of the Chessbase databases, but for now I was just looking for a large free collection of games.


The largest free database I could find was Caïssabase. This is a great resource. The games are not annotated like you would get with the Mega database, but there is a huge number of curated games. There are no games with less than 5 moves, the goal is to have games at least master strength, and there are no duplicates (as much as possible with 5 million games).

As of the latest version I have (updated in December 2022), here are some statistics:

  • 4.87 Million Games
  • Database last updated December 2022
  • The latest games are from December 19, 2022
  • The earliest game is from a game in Rome in the year 1610, Giulio Cesare Polerio vs Domenico.

Downloading and Using

First, find the correct download from the Caïssabase website. You will get a .zip file that is almost 500 MB. The files are in the SCID database format.

If you are using SCID (or SCIDvsPC/SCIDvsMac), you are ready to use this. Just open the database in SCID and you are set.

If you want to use this in Chessbase, there are a couple more steps.

Importing into Chessbase

You will need to use SCID to do get this database into a format that can be used for Chessbase. Download that free softare if you do not have it already. Then, just follow these steps:

  1. Open database in SCID
  2. Export PGN for all games
  3. Wait - This takes about 5 minutes on my computer, but it depends on how fast your computer is.

Now you have a large (over 3 GB) PGN file. You can use that for Chessbase, but it is faster if you convert it to a Chessbase format. Starting in Chessbase 17 you should use the 2CBH format, otherwise use the CBH.

  1. Open Chessbase and import that huge PGN file you created above.
  2. Convert to 2CBH or CBH format.
  3. Wait - this took me about 45 minutes on my computer
  4. (Optional) Make this your reference database by editing the properties.
  5. (Optional) If you are using a CBH format, you should also create a search booster under the “Maintenance” toolbar.
  6. (Optional) You can check for duplicate games using Chessbase’s maintenance feature - when I did it I found about 36k games.

If you use 2CBH, you will end up with about 5 GB of files. CBH format will be smaller, but also slower.

Now I can use this reference database for studying openings or reviewing historic games. I hope this database will continue to be updated so I can keep getting new games.