How to Pretty-Print JSON from curl — jq, Python & Browser Tools

Why curl output is hard to read

When you hit an API with curl, the JSON response comes back as a single line.

curl -s https://api.example.com/users/1

{"id":1,"name":"Tanaka","email":"tanaka@example.com","address":{"city":"Tokyo","zip":"100-0001"},"roles":["admin","editor"]}

No line breaks, no indentation. As nesting increases, this becomes impossible to scan. Here are four ways to turn that wall of text into readable JSON.

Pretty-print with jq

jq is the most popular command-line JSON processor.

Installing jq

# macOS
brew install jq

# Ubuntu / Debian
sudo apt install jq

# Windows (Chocolatey)
choco install jq

Basic usage

Pipe curl output into jq with a dot filter.

curl -s https://api.example.com/users/1 | jq .

{
  "id": 1,
  "name": "Tanaka",
  "email": "tanaka@example.com",
  "address": {
    "city": "Tokyo",
    "zip": "100-0001"
  },
  "roles": [
    "admin",
    "editor"
  ]
}

The -s flag silences curl's progress bar so only JSON reaches jq.

Useful filters

jq does more than pretty-printing. It can extract specific fields from the response.

Extract a single key:

curl -s https://api.example.com/users/1 | jq '.name'

"Tanaka"

Access nested keys with dot notation:

curl -s https://api.example.com/users/1 | jq '.address.city'

"Tokyo"

Pull a field from every element in an array:

curl -s https://api.example.com/users | jq '.[].name'

"Tanaka"
"Suzuki"
"Sato"

Filter elements by condition with select:

curl -s https://api.example.com/users | jq '.[] | select(.roles[] == "admin")'

Pretty-print with Python json.tool

If Python is already installed, you don't need any extra tools. The standard library includes json.tool.

curl -s https://api.example.com/users/1 | python3 -m json.tool

{
    "id": 1,
    "name": "Tanaka",
    "email": "tanaka@example.com",
    "address": {
        "city": "Tokyo",
        "zip": "100-0001"
    },
    "roles": [
        "admin",
        "editor"
    ]
}

It doesn't have jq's filtering capabilities, but for quick formatting it does the job. On systems with Python 2 only, use python instead of python3.

Pretty-print with formatarc CLI

Installation and usage

formatarc runs instantly via npx with no installation required.

curl -s https://api.example.com/users/1 | npx formatarc json-format

{
  "id": 1,
  "name": "Tanaka",
  "email": "tanaka@example.com",
  "address": {
    "city": "Tokyo",
    "zip": "100-0001"
  },
  "roles": [
    "admin",
    "editor"
  ]
}

For frequent use, install it globally to skip the npx startup time.

npm install -g formatarc
curl -s https://api.example.com/users/1 | formatarc json-format

Pipe to YAML or CSV

formatarc can also convert the JSON output to YAML or CSV in the same pipeline.

curl -s https://api.example.com/users/1 | npx formatarc json-to-yaml

id: 1
name: Tanaka
email: tanaka@example.com
address:
  city: Tokyo
  zip: "100-0001"
roles:
  - admin
  - editor

See the formatarc CLI guide for the full list of commands and options.

Format in the browser

Using FormatArc JSON Formatter

If you prefer not to use the command line, copy the curl output and paste it into JSON Formatter.

1. Copy the curl response
2. Open FormatArc JSON Formatter
3. Paste into the left text area
4. Click "Format"

The formatted result can be copied or converted to YAML / CSV directly from the tool.

Handling parse errors

If the JSON contains syntax errors, formatting will fail. Common causes and fixes are covered in How to Fix JSON Parse Errors.

Which method to choose

Method	Installation	Filtering	Best for
jq	Required	Powerful	Developers who work with APIs daily
Python json.tool	None (needs Python)	None	Quick formatting without extra tools
formatarc CLI	npx (instant)	None (conversion only)	When you also need YAML/CSV conversion
Browser (FormatArc)	None	None	Non-CLI users or one-off formatting

Using jq for everyday work and adding formatarc CLI when you need format conversion is an efficient combination.

Related articles

• JSON Formatting Tips
• formatarc CLI Guide
• How to Fix JSON Parse Errors
• JSON Syntax Guide

Summary

This article covered four ways to pretty-print JSON from curl: jq, Python's json.tool, formatarc CLI, and browser-based tools. jq is the most capable option with its filtering features. Python's json.tool requires no installation on most systems. formatarc CLI adds YAML and CSV conversion to the pipeline. For a visual approach, try FormatArc JSON Formatter.