You closed the wrong window. Don't reopen anything yet. Work through these steps in order.
1. Reopen with the shortcut
Press Ctrl+Shift+T (Cmd+Shift+T on Mac). Chrome reopens the most recently closed tab or window. Press it again to go further back.
2. Use the menu
Open the Chrome menu, choose History, and look at Recently closed. A whole closed window appears as a single entry, such as "12 tabs", so one click restores all of it.
3. Search your history
Open chrome://history and search for a keyword from the page. This works for individual pages, though not for rebuilding a window with its group layout.
4. Check what Chrome restores on startup
If Chrome closed because of a crash, look for the Restore prompt on next launch. Setting On startup to Continue where you left off also helps.
5. Use automatic snapshots
History only covers recent activity. A session manager keeps its own copies. KeepIt takes background snapshots every few minutes, and the Recover Closed option in its Tools menu lists recently closed windows and tabs you can bring back.
Prevent the next one
- Save important windows as named sessions before big changes.
- Turn on auto-save so you don't depend on remembering.
- Pin the tabs you can never afford to lose.
Ten seconds of setup now saves an afternoon of searching later.