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Open a OSK archive online, free

Open and extract .OSK archives online. Unzip, browse and download the files inside, free OSK extractor.

Drop your .OSK file here

Opens your .OSK file right here.

Choose .OSK file
Up to 2 GB · only the files you open are unpacked
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How to open a .OSK file online

No extra software to download or install.

01

Pick your .OSK file

Drag it in or click to choose it. We read its contents list first, so it opens right away without unpacking everything.

02

Browse what's inside

See every file with its size, how much it's compressed and its date, and search by name across all the folders.

03

Preview or download

Click a file to preview text or images, or save just that one. Need everything? Download it all as a single ZIP.

About .OSK files

What a .OSK file is, and what's inside it.

An OSK file is a game file used by the rhythm game osu! and developed by peppy. It functions as an archive that contains custom skin elements to change the visual appearance of the game's interface. These files are primarily opened and processed by the osu! application.

Programs that open .OSK files

Windows
osu!, WinRAR, 7-Zip
macOS
The Unarchiver, osu! (lazer)
Linux
osu! (lazer)
Android
osu!(lazer) for Android
iOS
osu!(lazer) for iOS
.OSK format details
Full nameosu! Skin Package
Developerpeppy (Dean Herbert); osu! game
First released2007 (osu! first released September 2007)
CategoryArchives
MIME typeapplication/zip
Signature50 4B 03 04 "PK" - standard ZIP local file header

Related viewers

Found something inside the archive? Open it here.

Do I have to unpack the whole .OSK file?

No. The viewer reads its table of contents first and only unpacks a file when you click it. That works even with multi-gigabyte archives, because we read just the bytes we need.

Can I open password-protected archives?

Yes, for ZIP (ZipCrypto and AES) and 7Z. You'll be asked for the password,. We can't recover forgotten passwords.

Is my .OSK file uploaded anywhere?

No. The code that unpacks the file is downloaded once and then reused.

Why does a .docx or .apk open as an archive?

Because they are ZIP archives under the hood. Office documents, Android apps, Java programs and EPUB books all use ZIP as their container.

What about split archives (.001, .z01, .part1.rar)?

Multi-part archives need all their parts. Today you can open the first part to see the file list; joining parts is on our roadmap.

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