Is my Serato database corrupt, and how do I fix it?

What the Serato database actually is

Serato DJ Pro 4 moved the library into a database called master.sqlite (with a companion, root.sqlite) inside ~/Library/Application Support/Serato/Library. That is the library Serato actually runs from. It still writes a database V2 file and .crate files into ~/Music/_Serato_, but those are exports for compatibility, which is why renaming database V2 does not reset a Serato 4 library. The full map of both folders is in what is in the _Serato_ folder, and if crates vanished right after updating, start with crates missing after a Serato 4 or 5 update.

Serato 4 also backs up master.sqlite automatically, into the Backups folder next to it: 15 minutes after you open the library, every 24 hours after that, and whenever the database structure changes. Each backup is a zip named with its date, such as master.sqlite-backup-20260925_110441+0300.zip. Serato has no restore button, so restoring means swapping the file by hand as in the steps above, and anything you changed after that backup is lost.

Serato DJ Pro 3.x and earlier keep everything inside ~/Music/_Serato_:

• database V2: one file holding the master index of every track Serato knows about, with its path, analysis state and cached overview.
• The Subcrates folder: one small .crate file per crate. Your crate structure lives here, not in the database.
• The History folder: your session history, again separate from the database.

On every version, cue points, saved loops and beatgrids are written into each audio file’s own tags. That separation is why a corrupt database is recoverable: the database is rebuildable, not the only copy of your work.

Symptoms that point to a corrupt database

• Serato crashes during launch, or hangs forever at the library loading stage.
• Crates appear empty even though the audio files exist and play elsewhere.
• The library loads but scrolling or searching stutters far more than usual.
• Analysis restarts from scratch every launch, or the same tracks re-analyze endlessly.
• Changes do not stick: you edit crates or tags, restart, and the edits are gone.

Before blaming the database, rule out hardware. A failing external drive or a bad USB cable produces identical symptoms, and rebuilding a database on a dying drive just corrupts the new one too. If the drive makes noise, disconnects randomly, or is slow in Finder as well, deal with the drive first.

What usually corrupts it

The database is rewritten while Serato runs, and anything that interrupts a write can damage it: force-quitting Serato mid-session, a power cut, unplugging the music drive while Serato is open, or the disk filling up completely. Two habits prevent most of it: always quit Serato properly before ejecting drives or shutting down, and keep enough free space on the drive that holds your Serato folders.

Corrupt files are not a corrupt database

Serato also flags individual tracks with a corrupt-file warning icon. That is a different problem: the audio file itself has damaged frames or malformed tags, usually from a bad download or an interrupted encode. A handful of corrupt files will not take your database down, but they can crash a deck when loaded mid-set, which is arguably worse. The closely related case, where Serato refuses to analyze a file at all, is covered in why Serato won't analyze some files.

The fix per track is to re-download or re-encode the file, then rescan its tags. The hard part is knowing how many corrupt files you have before one surprises you at a gig. Crate Cleaner scans your whole Serato library and flags corrupt files as one of the four signals in its health score, alongside missing files, duplicates and tracks that sit in no crate, so you get the complete list in one pass instead of discovering them one deck-load at a time. If a rebuild leaves tracks orange, Library Repair relinks them. The scan is read-only and the free plan requires no card.

Try Crate Cleaner free →

If the rebuild does not fix it

• Corruption returns within days: suspect the drive. Run First Aid in Disk Utility and check the drive's health before rebuilding again.
• Crates are damaged too: individual .crate files can corrupt, though it is rarer. Restore just the affected .crate files from your backup into the Subcrates folder.
• Serato still crashes with a fresh database: the problem is likely a corrupt audio file that crashes the importer. Re-add your music in halves to bisect which folder contains the culprit, then narrow it down. For crashes that are not about the database at all, see why Serato keeps crashing or freezing.
• Serato says the library failed to open: that is usually the drive, not the database. Check permissions, format and free space first, as in Serato library failed to open.

Make the next corruption a non-event

A corrupt database costs you an evening only if you have no backup. With one, it costs five minutes. Back up both Serato folders on a schedule, and always before big library surgery. The full routine, including what Serato's own auto-backup does and does not cover, is here: how to back up your Serato library.

FAQ

Will rebuilding the database delete my crates? No. Crates are also stored as separate .crate files in the Subcrates folder, which neither fix touches. On Serato 4, crates you made after the backup you restore may need recreating.

Do I lose my cue points and beatgrids? No. Cues, loops and grids are saved in each audio file's own tags. Re-importing the files reads them back. What you lose is cached analysis overviews, which rebuild when you re-analyze.

Should I delete the whole _Serato_ folder? Almost never. That deletes your crates along with the database. On Serato 3.x rename only the database V2 file; on Serato 4 restore master.sqlite from a backup instead.

Why does my database keep corrupting? Repeated corruption usually means an unreliable drive or a habit of force-quitting Serato or pulling drives while it runs. Check the disk with First Aid and always quit Serato before ejecting.

Can a corrupt track crash Serato even if the database is fine? Yes. A file with damaged frames can crash a deck when loaded. Scan for corrupt files periodically so none of them are waiting for you mid-set.