Line Counter + Unique Value Counter

What it does

Paste any list of text — one value per line (emails, IPs, usernames, log lines, whatever) — and instantly get:

• Total lines
• Non-empty lines
• Empty lines
• Unique values
• Duplicate values (and how many times each one appears)

Everything runs entirely in your browser — nothing you paste is ever sent anywhere.

Try it

How it works

1. Your input is split into lines using \n as the separator (handles both \n and \r\n line endings).
2. Depending on your chosen options, each line may be trimmed of leading and trailing whitespace, and/or compared case-insensitively.
3. Empty lines are counted separately, and — by default — excluded from the unique/duplicate analysis (toggle the checkbox to include them).
4. A Map is used to count occurrences of each distinct value. Anything appearing more than once is listed in the duplicates box along with its count; everything else (including values that appear exactly once) is listed in the unique values box.

Notes

• The unique values list preserves the first occurrence's original casing/formatting (not the normalized version used for comparison).
• This tool is great for cleaning up mailing lists, deduplicating IP/host lists, checking for repeated entries in log files, or verifying that a generated list has no duplicates before importing it somewhere else.