Text File Generator
A line counter answers a question that sounds simple until you try to do it by hand. Paste your text and you get the total straight away, along with how many of those lines are blank, how many are genuinely unique, how many repeat, and how long the longest and shortest ones run.
Blank lines are the usual argument
Ask two people to count the lines in a file and they will often disagree by exactly the number of empty lines in it. A text editor counts every line including the empty ones, because it is showing you positions. Someone counting records in an export wants the empty ones ignored, because a blank line is not a record.
Rather than pick a side, the counter shows both and lets you decide which one is the answer. Tick the blank line option and the headline figure switches to the non-empty count while the raw total stays visible underneath it.
Finding repeated lines in a list
The unique and duplicate figures are what make this useful for list work. A list of two thousand email addresses that reports 1,847 unique lines has just told you something important, and it took a paste to find out.
Trailing spaces are the sneaky part of that. Two lines that look identical on screen are treated as different if one of them ends in a space, which is exactly how an export from a spreadsheet tends to arrive. Turn on trimming and the comparison happens after those invisible characters are stripped, which usually makes the duplicate count jump.
Line length figures and where they help
The longest line measurement earns its keep with fixed width data and imports. When a system rejects a file for exceeding a field width, the offending row is nearly always the longest line, and knowing it runs to 312 characters when the limit is 255 saves you scrolling through the file to find it.
Average line length is a quieter signal. On a CSV export, a wildly different average between two files usually means the column structure changed somewhere between them. Once you know how many lines you are dealing with, the add line numbers tool is the natural next step if you need to reference specific rows.