To check the signature of a file, in other words its MD5 fingerprint (checksum).
HTML5 File Hash Online Calculator
Download winmd5free. Install it and then click the Browse button to select your file. Enter the checksum recommended on this page (See Adding Bios) by putting it in the Original file MD5 box and then click Verify.
EXAMPLE: gba_bios.bin
Since Powershell v4.0 (Windows 8.1 and above), the get-filehash command allows you to natively check the checksum of a file.
Get-FileHash "file to verify" -Algorithm MD5
To test all the files in a folder (recursively), run the following command after moving to the directory:
Get-ChildItem -recurse | % {Get-FileHash $_.Fullname -Algorithm MD5} | select Path,Hash | ft -AutoSize
You can also download this script: HackCheck Shell Extension Which allows you to add an extra tab in the properties of a file for Windows 10.
Use the command md5sum.
In terminal, to check the checksum of bios files, use the command shasum followed by the file name.