wc Command on Linux: Count Lines, Words and Bytes in Files

wc on Linux is the fastest sanity check — “how many lines in this log?”, “did my export have the expected row count?”, “is this file empty?” Scripts often store lines=$(wc -l < file) for loops and validation.

Pair with: split,
grep,
tee.

Default output

Shows lines, words, and bytes unless you pass flags only.

wc /var/log/syslog

Lines only

-l is the most used flag for scripts and pipelines.

wc -l access.log
grep ERROR app.log | wc -l

Bytes and chars

-c bytes; -m characters (locale-aware Unicode).

wc -c image.bin

Pipes and variables

Reading from stdin avoids filename in the count line.

Quick Reference

• Lines: wc -l file
• Pipe: cmd | wc -l
• Script: lines=$(wc -l < file)

Related tutorials

• split
• find
• read CSV

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