Search for Files by Name with locate in Linux

Learn how locate searches a filename database, refresh it with updatedb, troubleshoot stale results, and choose locate or find for Linux file searches.

The locate command searches for filesystem paths and filenames that contain specified text. It is designed for fast filename searches, not for detailed filtering by permissions, ownership, size, or timestamps.

This lesson assumes familiarity with the Linux terminal, shell commands, files, directories, and basic sudo use. For background on paths and directories, see File Structure in Linux.

What locate Does

The basic command structure is:

locate SEARCH_TERM

locate finds indexed paths whose names or path text match SEARCH_TERM. It does not normally walk through every directory during each search. Instead, it reads a prebuilt locate database, which is an index containing filesystem paths and filenames.

Because the command looks up text in an index rather than performing a live filesystem search, it usually responds very quickly. This makes it useful when you remember part of a filename and want possible matching paths.

Basic Filename Searches

Search for a specific filename

To search for paths containing notes.txt, run:

locate notes.txt

The output may contain one or many paths. For example:

/home/alex/notes.txt
/home/alex/Documents/notes.txt
/home/alex/old-notes.txt

The command searches for the supplied text in indexed paths. Therefore, a result does not necessarily mean that the final component of the path is exactly the search term. A path such as /home/alex/old-notes.txt can also match because it contains notes.txt.

Search with a name fragment

You can search for part of a name, such as:

locate log

This can return paths containing log, including names such as system.log, catalog, or directories with log in their path. Broad terms can produce many results, so use a more specific filename or path fragment when possible.

How the locate Database Works

A system periodically builds or refreshes the locate database by examining filesystem paths. The schedule depends on the system configuration; it may run daily, weekly, or on another maintenance schedule.

When you run locate, the command consults the saved index. It does not perform a live filesystem search, meaning it does not inspect the current state of every directory at command execution time.

This design explains both of locate's main characteristics:

Fast results: searching an index is generally faster than traversing the filesystem.
Possibly stale results: the index can differ from what currently exists on disk.

Why Recent Files May Be Missing

Suppose you create a file and immediately search for it:

touch recent-file.txt
locate recent-file.txt

The file exists on the live filesystem, but the command may print no output. The database might have been created before recent-file.txt existed, so the new path is not indexed yet.

The same issue can occur when a file has recently been moved or renamed. The old location may remain in the database while the new location is absent until the next database update. Conversely, a deleted file can continue to appear in locate output while its old entry remains indexed.

Situation	Likely reason	Recommended action
File was created recently	The database predates the file.	Refresh the database with `updatedb`, then search again.
File was moved or renamed recently	The index still has the old path and may not have the new path.	Refresh the database or use `find` for a current search.
File was deleted but still appears	An older path entry remains in the index.	Refresh the database or verify the live filesystem with `find`.
Database update has not run yet	The scheduled maintenance task has not refreshed the index.	Run `updatedb` manually if authorized.

Refreshing the Database with updatedb

updatedb creates or refreshes the database used by locate. Run it before repeating a search when the index is out of date:

sudo updatedb
locate recent-file.txt

After updatedb completes, the newly created file should be included in the index, and the second command can return its path.

Administrative permissions may be required because the update can inspect many parts of the system and create a system-wide database. On systems where the current user is permitted to update the database directly, the command may work without sudo:

updatedb

If the command is rejected because of permissions, use sudo updatedb when your account is authorized, or follow your system administrator's policy.

locate Compared with find

find performs a live filesystem search. It traverses directories and evaluates the current filesystem state while the command runs. This can take longer, especially when starting at the root directory, but its results reflect changes that have already occurred.

locate notes.txt
find / -name 'notes.txt' 2>/dev/null

The first command queries the locate database. The second command starts at /, searches the filesystem directly, and hides many permission-denied messages by redirecting standard error to /dev/null.

Characteristic	locate	find
Search method	Queries a prebuilt filename and path database.	Traverses the filesystem and evaluates entries live.
Speed	Generally very fast for name and path lookups.	Can be slower because it examines directories during the search.
Data freshness	Can be stale until the database is updated.	Reflects the filesystem state at search time.
Primary search criteria	Names and path text.	Names, paths, file types, times, sizes, permissions, ownership, and more.
Filter by permissions, owner, and size	Not its intended purpose.	Yes, using appropriate find predicates.
Typical use case	Quickly find possible paths from a remembered filename or fragment.	Perform a current search or apply detailed file-property conditions.

Use locate when speed and filename matching are the main requirements. Use find when accuracy against the current filesystem or attribute filtering matters. For example, file ownership concepts are covered in Manage File Ownership.

Troubleshooting locate

No result for a file that was just created

Cause: The database was built before the file existed.

Fix:

sudo updatedb
locate recent-file.txt

A result points to a file that no longer exists

Cause: The database contains an older path entry.

Fix: Refresh the index with updatedb, or use find to check the live filesystem.

Too many results appear

Cause: The search term is a common fragment that occurs in many indexed paths.

Fix: Use a more specific term, such as a complete filename or a distinctive directory name:

locate project-notes.txt

updatedb cannot be run

Cause: The system-wide database requires elevated privileges.

Fix: Run sudo updatedb if you are authorized. If your account cannot use sudo, ask the administrator or wait for the configured maintenance update.

The search depends on permissions, ownership, or size

Cause: locate is intended for indexed filename and path matching, not detailed live attributes.

Fix: Use find with the appropriate filters. A live search is also preferable when you must be certain that results reflect the current filesystem.

Practical Decision Guide

Need a quick search based on a filename or path fragment? Use locate SEARCH_TERM.
Did the file change recently or must the result be current? Use find, or refresh the index first with updatedb.
Need to filter by permissions, owner, size, timestamps, or file type? Use find.
Did a broad search return too many paths? Replace the common fragment with a more specific filename.

Key Points

locate searches indexed filenames and paths.
Its database-based design usually makes it faster than a live traversal.
New, moved, renamed, or deleted files may not be represented immediately.
updatedb refreshes the database; sudo may be required.
find searches the live filesystem and supports detailed attribute filters.