I think it is a good time to post an article about a free hash/checksum calculator tool because so many impatient IT pros have to compute the checksum of Windows 7 RTM now. There are many such tools out there, but HashCalc is probably the most comprehensive free hash sum computation utility. It supports 13 popular hash and checksum algorithms: MD2, MD4, MD5, SHA-1, SHA-2( 256, 384, 512), RIPEMD-160, PANAMA, TIGER, ADLER32, CRC32, and HMAC. Crypto purists probably will say that HMAC is not really a hash function though.
The download page doesn’t mention Vista as supported OS, but it works fine also on Vista x64. HashCalc calculates checksums of files, text strings and hex strings. SlavaSoft, HashCalc’s publisher, claims you can compute the hashes of files sizes up to 15GB.
I tested HashCalc 2.02.