JSON pretty print

The equivalent in every language you might reach for

Pretty printing is the operation you have written a one-liner for in every language. For reference, and because the flags are easy to forget:

# jq — 2-space indent by default, -S also sorts keys
jq . data.json
jq -S . data.json

# Python
python -m json.tool --indent 2 data.json
python -c "import json,sys; print(json.dumps(json.load(sys.stdin), indent=2, sort_keys=True))"

# Node
node -e "console.log(JSON.stringify(require('./data.json'), null, 2))"

# Go
json.Indent(&out, in, "", "  ")          // or json.MarshalIndent(v, "", "  ")

# Ruby
ruby -rjson -e 'puts JSON.pretty_generate(JSON.parse(STDIN.read))'

# PowerShell
Get-Content data.json | ConvertFrom-Json | ConvertTo-Json -Depth 100

# curl, straight into a pretty printer
curl -s https://api.example.com/v2/orders | jq .

All of them produce the same shape of output. The differences worth knowing:ConvertTo-Json defaults to a depth of 2 and silently truncates deeper structures unless you pass -Depth; Go’s MarshalIndent escapes <,>, and & inside strings as the escape sequences\u003c, \u003e, and \u0026unless you call SetEscapeHTML(false) on the encoder; and Python sorts keys only when you ask.

When the browser is the better tool

The command line wins for files and pipelines. This page wins when:

• The JSON is on your clipboard, not on disk, and you do not want a temporary file just to read it.
• The document is long enough that reading indented text is the wrong interface, and you would rather click through a tree.
• It does not parse yet, and you want the line, the column, and a caret rather thanparse error: Expected separator between values at line 1, column 20.
• The payload contains credentials or customer data you would rather not paste into a web service that posts it to a backend. Nothing here is uploaded.

Indentation and diffs

Pretty printing exists to make JSON reviewable, and the indent width you choose has a direct effect on that. Two spaces keeps deeply nested documents inside a reasonable line length, which matters because JSON nests fast — five levels at four spaces starts every line twenty columns in.

If you pretty print JSON that is checked into version control, pick one width and one key order and stay with them. Re-printing the same data with different settings produces a diff that touches every line and communicates nothing. Sort keys is the reliable way to make two documents comparable when they came from sources that emit properties in different orders.