Where Are macOS Unified Logs Stored?
Unified logs live in tracev3 files under /var/db/diagnostics and supporting text data under /var/db/uuidtext. Use the log command to read them.
Last updated
macOS writes unified logging data to /var/db/diagnostics as tracev3 archives. Supplementary identifier text lives in /var/db/uuidtext.
Files are owned by root and protected by SIP. The log tool assembles entries at query time, so copying raw tracev3 files alone often gives incomplete results.
Where macOS stores this, by platform
/var/db/diagnostics
Main store for system and app tracev3 data. Requires root or sudo to list and collect. Use log collect or sysdiagnose to export a complete set with metadata.
/var/db/uuidtext
Holds uuidtext files that map binary log data to readable strings. Missing uuidtext makes copied tracev3 files hard to decode. Collect both folders together for offline review.
Frequently asked questions
How do I read unified logs without copying raw files?
Run log show or log stream with predicates and time bounds in Terminal. Use sudo for system domains and redirect output to a file for review.
Why do tracev3 files look incomplete on another Mac?
Entries need uuidtext and related support files to render fully. Use log collect or sysdiagnose on the source Mac to bundle all parts.
Notice an outdated path? Let us know.