Day One stores your entries and photos locally on each device. If you are using Day One Sync, your data is also stored on the Day One Sync server.
Day One
iOS/Android
Data is stored locally on your iPhone/iPad/Android hard drive. It is not accessible by the user other than through the app.
macOS
The data is stored in this location on your Mac: ~/Library/Group Containers/5U8NS4GX82.dayoneapp2
We do not recommend making changes to the data outside of the app. If you are sharing a computer will others, we also recommend using separate User Profiles to access accounts and FileVault to encrypt your local data on the hard drive.
Day One Classic
The easiest way to find your journal file on Mac in Finder is:
Open Day One Preferences (Day One > Preferences)
Click the “Sync” tab
Click the displayed path and it will be revealed in Finder
To view the files, hold down the control key and click “Journal.dayone,” then choose “Show Package Contents.”
The default journal locations are:
iCloud Sync: ~/Library/Mobile Documents/5U8NS4GX82~com~dayoneapp~dayone/Documents/Journal_dayone
Dropbox Sync: ~/Dropbox/Apps/Day One/Journal.dayone
Day One Sync: ~/Library/Group Containers/5U8NS4GX82.dayoneapp/Data/Documents/Journal.dayone
Local filesystem (v1.7 and later) – sync disabled: ~/Library/Group Containers/5U8NS4GX82.dayoneapp/Data/Documents/Journal.dayone
Local filesystem (v1.5.5 and earlier) – sync disabled: ~/Library/Application Support/Day One/Journal.dayone
To view the files, hold down the control key and click “Journal.dayone,” then choose “Show Package Contents.”
If you are unable to get to your journal file from within Day One, you will have to navigate to the local paths above, using the Finder’s “Go to Folder” function. Copy the appropriate path from the above options, then go to Finder and select Go > Go to Folder. In the dialogue box that appears, paste the file path, then click Go. The Finder window will now display the journal_dayone folder or journal.dayone package.