Open a SQL Server .bak file without SQL Server

What this tool shows

It shows the details that SQL Server's RESTORE HEADERONLY and RESTORE FILELISTONLY commands return, without needing SQL Server. Drop a backup onto the box above to see them.

For each backup you get:

• The database name, its compatibility level and recovery model.
• The kind of backup: full, differential, log or file/filegroup, and whether it is copy-only.
• When the backup started and finished, its exact size, and whether it is compressed or has checksums.
• The server and machine it came from, and that server's SQL Server version and build.
• The oldest SQL Server version that can restore it.
• Every database file in the backup, with its logical name, type, filegroup, size and original path.
• A ready-made RESTORE DATABASE command.

You can copy the details as JSON or download them as a text report. The field names in the JSON match SQL Server's own column names, such as DatabaseName and BackupStartDate.

Which SQL Server version do I need to restore a .bak file?

You need the same SQL Server version that made the backup, or a newer one. You can't restore a backup to an older version of SQL Server.

The summary line above tells you the version needed. It comes from a database version number stored in the backup. This table shows how those numbers map to releases:

The details also show which version the source server was running, for example "SQL Server 2019 (15.0.2000)". Backups made by SQL Server 2000 to 2008 R2 are read on a best effort basis.

Going the other way also has limits. The newest SQL Server releases can't restore very old backups directly, so check Microsoft's documentation if your backup comes from SQL Server 2000 or 2005.

How to restore the backup

Copy the restore command the tool makes and run it on a SQL Server instance of the right version. If you don't have one, SQL Server Express and SQL Server Developer edition are both free from Microsoft.

The command looks like this:

RESTORE DATABASE [Sales]
FROM DISK = N'Sales.bak'
WITH MOVE N'Sales' TO N'<your data folder>\Sales.mdf',
     MOVE N'Sales_log' TO N'<your data folder>\Sales_log.ldf',
     STATS = 5;

• FROM DISK is the backup file. Use its full path on the server.
• Each MOVE line puts one database file in a new place. Replace <your data folder> with a folder on your server, because the original paths usually don't exist on another machine.
• STATS = 5 prints progress every 5 percent.
• For a striped backup, the command lists every stripe file, and you need all of them.

A differential or log backup can't be restored on its own. Restore the full backup first, then the latest differential, then each log backup in order. Add NORECOVERY to the WITH options of every step except the last. It leaves the database waiting for the next backup. When you open a differential or log backup, the tool adds a reminder to the command, and for a log backup it writes RESTORE LOG instead of RESTORE DATABASE.

SQL Server itself runs on Windows and Linux. To restore on a Mac, run it in a Linux container or a virtual machine.

Why some backups can't be read

Encrypted backups can only be read by a server that has the right certificate, so the tool shows just that the backup is encrypted. Backups made by other backup products use their own formats.

• Encrypted backups. The tool shows that the file is encrypted and the thumbprint of the certificate or key that encrypted it. Use the thumbprint to find the certificate you need on the server. The rest of the details can't be read without it.
• Other backup products. Some third-party backup tools write their own formats. The tool recognises some of them and tells you to open the file with that product's own tools. Others show as not a SQL Server backup.
• Damaged files. If part of the file is missing or corrupt, the tool says so and shows whatever it could read.
• QAT_DEFLATE compression. Backups compressed with Intel QuickAssist are not supported yet.

Is it safe? Your file never leaves your computer

Yes. The tool reads your backup inside your browser tab and never uploads it. It reads only the start and end of the file, and the page has no server that could receive it.

A backup can hold server names, user names and file paths. They appear only on your screen. To check that nothing is sent:

1. Open your browser's developer tools (F12, or Cmd+Option+I on a Mac) and go to the Network tab.
2. Clear the list, then open your backup file in the tool.
3. Look at the requests that appear. You will not see your file being sent anywhere.

You can also disconnect from the internet after the page has loaded and the tool will still open your file. The privacy page has more detail.