.apk — Android Package
Executable application/vnd.android.package-archive
What a .apk file is
An Android application package — a signed ZIP containing compiled code, resources and a manifest.
How to open it
Android devices, with "install from unknown sources" enabled for sideloading.
Worth knowing
Sideloaded APKs bypass Play Store review entirely. Only install ones whose signature you can verify.
How to identify a .apk file
A file's extension is only its name — renaming a.png to a.apk changes nothing inside. What software actually reads is the magic number, the first few bytes of the file.
| Signature | 50 4B 03 04 |
| MIME type | application/vnd.android.package-archive |
| Category | Executable |
A ZIP again — Android packages are ZIP archives.
# what is this file really?
file mystery.apk
# look at the first bytes yourself
xxd mystery.apk | head -2
head -c 16 mystery.apk | xxd
# Windows PowerShell
Get-Content mystery.apk -AsByteStream -TotalCount 16 | Format-HexFrequently asked questions
What is a .apk file?
An Android application package — a signed ZIP containing compiled code, resources and a manifest.
How do I open a .apk file?
Android devices, with "install from unknown sources" enabled for sideloading.
Is .apk safe to open?
No — not from an untrusted source. A .apk file is executable code, and opening one runs it. Check the digital signature first, and prefer official distribution channels.
Can I change a file's extension to convert it?
No. Renaming changes the label, not the bytes. The one place it appears to work is between formats that genuinely share a container — renaming .docx to .zip works because a DOCX is a ZIP. Everything else needs a real converter.