How to Sort and Deduplicate Text with sort and uniq

Published 2026-08-05 · Learn Linux

The sort command orders lines of text and uniq removes consecutive duplicates. sort names.txt prints the file alphabetically, and sort names.txt | uniq -c counts how often each line appears. Together they are the standard way to summarize lists.

Sort lines alphabetically

sort reads lines and prints them in order. The original file is untouched; the sorted result goes to the screen.

$ sort names.txt

Sort numbers with -n

Plain sort orders text, so 10 comes before 2. Add -n for numeric order and -r to reverse (largest first). This ranks sizes or scores correctly.

$ sort -n scores.txt

$ sort -nr scores.txt

Remove duplicates with uniq

uniq removes consecutive identical lines, so sort first to group duplicates together. The -c flag prepends the count of each line.

$ sort cities.txt | uniq

$ sort cities.txt | uniq -c

Sort by a column

Use -k to sort by a specific field. sort -k2 -n sorts by the second column numerically, which is how you rank table-like output.

$ sort -k2 -n data.tsv

Combine with other tools

sort is the perfect end of a pipe: rank the biggest folders with du, list log visitors with awk, then dedupe with uniq. See sort and uniq for details.