Explainshell

ExplainShell — Shell Command Explainer

Paste any shell command or one-liner and get a plain-English breakdown of every flag, argument, and pipe stage. Powered by explainshell.com, which maps commands to their man-page descriptions.

No API key required. Works immediately for any user.

When to Use

• User pastes a cryptic command and asks "what does this do?"
• Reviewing an unfamiliar bash script or automation pipeline
• Learning: user wants to understand each part of a complex one-liner
• Documentation: need to annotate shell commands in runbooks
• User asks "explain this command", "what does this flag mean?", "break this down"

How to Use

Explain a single command (browser link)

# The simplest approach — open the explanation in the browser
$command = "tar -xzf archive.tar.gz -C /tmp"
$encoded = [Uri]::EscapeDataString($command)
Start-Process "https://explainshell.com/explain?cmd=$encoded"
Write-Host "Opened: https://explainshell.com/explain?cmd=$encoded"

Fetch explanation text directly (PowerShell)

$command = "find . -type f -name '*.log' -mtime +7 -exec rm {} \;"
$encoded = [Uri]::EscapeDataString($command)
$url     = "https://explainshell.com/explain?cmd=$encoded"

$html    = Invoke-WebRequest -Uri $url -UseBasicParsing
# Extract helptext spans (plain text explanations)
$pattern = '<span class="helptext">(.*?)</span>'
$matches = [regex]::Matches($html.Content, $pattern, 'Singleline')

Write-Host "Command: $command"
Write-Host ""
$matches | ForEach-Object {
    $text = $_.Groups[1].Value -replace '<[^>]+>', '' -replace '&amp;', '&' -replace '&lt;', '<' -replace '&gt;', '>'
    if ($text.Trim()) { Write-Host "  • $($text.Trim())" }
}
Write-Host ""
Write-Host "Full explanation: $url"

Explain a piped one-liner

$command = "ps aux | awk '{print \$2, \$11}' | sort -k2 | uniq -c | sort -rn | head -10"
$encoded = [Uri]::EscapeDataString($command)
Write-Host "ExplainShell link:"
Write-Host "  https://explainshell.com/explain?cmd=$encoded"

Examples

"Explain: tar -xzf file.tar.gz" → tar: archive utility; -x: extract; -z: filter through gzip; -f: use archive file.

"What does find . -type f -exec rm {} \; do?" → find: search; .: starting directory; -type f: only files; -exec rm {} ;: run rm on each result.

"Break down: awk '{print $2}' | sort | uniq -c" → awk: text processor prints second field; sort: lexicographic sort; uniq -c: count consecutive duplicates.

"What is 2>&1 in a command?" → Redirects stderr (fd 2) to the same destination as stdout (fd 1) — merges error output.

Cautions

• explainshell.com covers most standard POSIX and GNU commands — may not know custom scripts or aliases
• Very long one-liners (> 200 chars) may produce incomplete explanations
• Some compound expressions (e.g. complex awk programs) parse partially
• Rate-limit: be polite — avoid bulk automated requests to a free community service
• The HTML structure may change; if parsing fails, the URL is always valid as a fallback

Requirements

• None — no API key needed
• Works with any POSIX/GNU shell command or pipeline