Neil Turner's Blog

Blogging about technology and randomness since 2002

Verifying MD5 checksums on a Mac

This is mostly for my own future reference, but if you need to verify an MD5 checksum on a Mac, you need to do this:

  1. Open Terminal
  2. Type openssl md5 [filename]

Change ‘md5’ to ‘sha1’ if you want to verify the SHA-1 hash as well.

I downloaded Windows Vista RC1 last night and so I needed to verify the MD5 hash before burning it to DVD-R. Apparently it does work with Boot Camp now (the betas didn’t) so I’ll be sticking it on my MacBook this afternoon, just as soon as I’ve bought a DVD-R. I didn’t opt for a SuperDrive on my MacBook so it can’t burn DVDs, but I’ve been at my parents’ this weekend and their computer does have a DVD-RW drive.
And though this will undoubtedly come as no surprise to most of you, but verifying an MD5 hash on a 2.52 GB file takes a long time.


  1. Hmmpf, I tried yet again to use Boot Camp to install Vista. Once again, I get the same message I get every other time I try to install it. That Boot Camp doesn’t recognize the disc.
    I understand now that Vista Beta 2 will install under Parallels, but who wants to use an older copy when RC1 is out.
    I tried installed RC1 with Parallels and got the message saying that the BIOS isn’t compatible.
    One of the biggest problems with Boot Camp, that I have found anyway, is that once you finish the attempt, trying to remove the partition you created doesn’t work. So I have to move the files off the drive I partitioned with Boot Camp and then repartition it.
    Disk Utility thinks there is just one partition, but OS X seems to not know where the 80GB’s I partitioned with Boot Camp is.
    I guess I’ll wait for Leopard for doing any Windows like things with my Mac Pro. Either that, or wait for Parallels to fix the problems with it. BTW, I now can’t access the web with Parallels on my Mac Pro. I haven’t tried using the new beta with my MacBook since it works fine for what I use it for there.

  2. You could simply type “md5 the_file_to_hash”…

  3. Yes, apparently you can… I was expecting the command to be ‘md5sum’ hence why I researched another solution. But you need to use the method I posted for SHA-1 checksums, however.

  4. Thanks for this note to yourself.

  5. Thanks for this blog post. I found it very useful 🙂