Unix command to check the filesize

Here's yet another option to add to the mix:

$ du -b file.txt

That is: estimate file space usage of file.txt in bytes.

ls -l --block-size=M 

will give you a long format listing (needed to actually see the file size) and round file sizes up to the nearest MiB. If you want MB (10^6 bytes) rather than MiB (2^20 bytes) units, use --block-size=MB instead.

Or

ls -lah 

-h When used with the -l option, use unit suffixes: Byte, Kilobyte, Megabyte, Gigabyte, Terabyte and Petabyte in order to reduce the number of digits to three or less using base 2 for sizes.

man ls

http://unixhelp.ed.ac.uk/CGI/man-cgi?ls

I hope ls -lah will do the job. Also if you are new to unix environment please go to http://www.tutorialspoint.com/unix/unix-useful-commands.htm

stat -c %s file.txt

This command will give you the size of the file in bytes. You can learn more about why you should avoid parsing output of ls command over here: http://mywiki.wooledge.org/ParsingLs