.dll

What is a .dll file?

A shared library file used by Windows programs.

Use caution
Type System
By Microsoft
MIME application/x-msdownload

Drop any file to identify it

We read file headers, not extensions. Nothing gets uploaded.

What is it

A shared library file used by Windows programs. DLLs contain code and data that multiple programs can use simultaneously, reducing memory usage and enabling modular software design. Missing or corrupted DLLs are a common source of Windows errors.

Technical details
Full Name
Dynamic Link Library
MIME Type
application/x-msdownload
Developer
Microsoft
Magic Bytes
4D 5A
Safety
.dll requires caution. DLL files contain executable code. Never download DLLs from untrusted websites — this is a common malware vector.
What opens it
Dependency Walker
FREE Windows
PE Explorer
PAID Windows
FAQ
Should I download DLL files from the internet?
No. Downloading DLLs from random websites is a major security risk. If you're missing a DLL, reinstall the software that needs it, or run Windows System File Checker (sfc /scannow).
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