Minecraft wiki entry for Screenshot, associated text: Screenshots are saved as .png files with a naming format based on the current date and time: YYYY-MM-DD_HH.MM.SS.png. For example, a screenshot taken on April 17, 2022, at 12:02:36 pm gets named "2022-04-17_12.02.36.png". If multiple screenshots are saved within the same second, a revision number is appended to the file name (e.g., "2022-04-17_12.02.36_1.png" is the second screenshot taken at that time).