MD5 File
Compute the MD5 checksum of any file. The file is streamed in chunks, so even multi-gigabyte files can be hashed without freezing the browser.
Calculate the MD5 checksum of a file. Free, offline, runs entirely in your browser. Read more Show less
What is a file checksum?
A file checksum is a fixed-length fingerprint of a file's contents. The same file always produces the same checksum; a single changed byte produces a completely different one. Checksums are used to verify downloads, detect corruption, and confirm two copies of a file are identical.
MD5 checksums are common in download pages and package managers. They are fast and adequate for detecting accidental changes, but they are not a security mechanism: MD5 is collision-broken, so an attacker can construct two different files with the same checksum.
How to use
Drag a file into the box, click to select one, or paste a file from the clipboard. The tool reads the file in small chunks and computes the MD5 as it goes, so memory use stays low and the browser remains responsive.
You can also enter a file URL. The server must allow cross-origin requests; if it does not, download the file and use the File tab.
FAQ
Are my files uploaded anywhere?
No. The file never leaves your device. Everything is done locally with the File API and a WebAssembly implementation of MD5.
How large a file can I hash?
Any size your browser can open. Files are streamed in chunks, so a 4 GB ISO works without using 4 GB of RAM. Speed depends on disk I/O and CPU.
Why does my checksum differ from another tool?
Confirm the file has not changed between runs, and that the other tool is not hashing something different (a zip wrapper, a trailing newline added by text mode). Read the file in binary mode in all tools.
Is MD5 good enough to verify a download?
Yes against accidental corruption. No against a malicious mirror: prefer SHA-256, or better, a signed checksum from the vendor.
Command line equivalent
# Linux / macOS
md5sum myfile.bin
# macOS (BSD)
md5 myfile.bin
# Windows PowerShell
Get-FileHash myfile.bin -Algorithm MD5The server must allow cross-origin requests (CORS). If it doesn't, download the file and use the File tab.