AudioGuru is a program that lets you see all relevant information (and not so relevant too) about audio files. With it, you can open an audio file to see all the metadata, like covert art, text lyrics, bitrate on a per-frame basis and scan it for errors.
It can be useful to compare your encoded files for compression rates. Also, if you have some audio files that play weird in some players, you can scan them with AudioGuru to check them.
You can integrate it in the explorer shell menu for easier access to scan files.
Support all the major audio formats, such as MP3, AC3, MP4, WavPack, MPC, APE, among others.

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Many sites list hashes, a unique file string based on different algorithms, for their file downloads so that every user can verify the integrity of those files, or even check if the file they got its the same that the one that is on the site.
HashTab makes this a snap by adding a tab called File Hashes to the properties window of every file. If you need to verify a file, right click on it, select Properties and click on File Hashes tab. It automatically hashes the file and shows the calculated string based on the algorithms you choose.
It supports the most used algorithms, including MD5 and CRC32. Another great use for this is to check pairs of files to see if they are identical, because this algorithms produce unique strings for every file, except when they are 100% identical..
I use this very often for patched files in unattended installations or if i want to check a file i got from somewhere else, comparing it with the hash provided in the official source.
HashTab does not support SFV (Simple File Verification) files. If you are looking for a program to check SFV files, i use SFVLite, which is great for checking this type of files.

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