jq Online Playground: Filter and Transform JSON in Your Browser (2026)

jq Online Playground: Filter and Transform JSON in Your Browser

jq is the Swiss Army knife of JSON processing. But installing it locally, configuring your PATH, and debugging filter syntax in a terminal is friction you don't always want.

Online jq playgrounds let you test filters immediately in the browser — paste JSON, write a filter, see the result. This guide covers the best options in 2026, the most useful jq patterns, and when to use online tools vs the command-line version.

What jq Does

jq is a lightweight, command-line JSON processor. Given a JSON input, you write a filter expression and jq applies it:

echo '{"name": "Alice", "score": 95}' | jq '.name'
# "Alice"

It can filter, transform, reshape, aggregate, and generate JSON from JSON. For developers working with APIs, LLM outputs, and data pipelines, it's one of the most useful tools available.

Best jq Online Playgrounds in 2026

Several good browser-based jq environments exist. The key differences are which version of jq they run, whether they support multiple files, and how fast they evaluate filters.

jq play (jqplay.org) — The original. Runs jq 1.7. Supports the --rawoutput (-r) flag and --slurp (-s) mode. Shareable URLs. The reference tool for the jq community. JSON Playground (jsonplayground.com) — Formats, validates, and queries JSON in one interface. Useful when you want formatting alongside jq filtering. DevToolsDailyq (devtoolsdaily.com/jq_playground) — Clean interface, WASM-based so it runs fully in-browser without server round trips. CodeTidy jq — Interactive playground with real-time evaluation as you type.

For most use cases, jqplay.org is the recommendation — it runs the actual jq binary and matches your local version exactly.

If you need to repair broken JSON before running jq, paste it into AI JSON Medic first — jq will fail on malformed input, so fix the structure before filtering.

jq Filter Syntax: The Essentials

Identity and field access

.                     # identity — output input unchanged
.name                 # get field "name"
.user.email           # nested field access
.["content-type"]     # field with hyphen or special chars

Array operations

.[0]                  # first element
.[-1]                 # last element
.[2:5]                # slice indices 2,3,4
.[]                   # explode — iterate all elements

Pipe and transform

.users | .[] | .name              # get all user names
.items | map(.price) | add        # sum all prices
.results | map(select(.active))   # filter active items

Type and conversion

type                  # string, number, boolean, null, array, object
length                # string length or array/object size
keys                  # object keys as array
values                # object values as array
to_entries            # [{key, value}] pairs
from_entries          # [{key, value}] → object

Real-World jq Patterns

Extract fields from API response

# Input: GitHub API user response
# Get login + public repo count
{login: .login, repos: .public_repos}

Filter array by condition

# Input: list of pull requests
# Get only open PRs by a specific user
.[] | select(.state == "open" and .user.login == "alice")

Reshape nested data

# Input: LLM structured output with nested tool calls
# Flatten to list of tool names and their arguments
.content[] | select(.type == "tool_use") | {tool: .name, input: .input}

Aggregate and compute

# Input: array of order objects with price field
# Sum total order value
[.[].price] | add

# Average
[.[].score] | add / length

Convert array to object (key by field)

# Input: array of {id, name} objects
# Output: {id → name} lookup object
[.[] | {(.id | tostring): .name}] | add

Using jq for LLM Output Processing

LLMs increasingly return structured JSON. jq is useful for extracting specific fields from those responses before passing them to downstream systems.

Extract from OpenAI chat completion

# Get the assistant message content
.choices[0].message.content

Extract from Anthropic messages API

# Get text from first content block
.content[] | select(.type == "text") | .text | head(1)

Extract tool use arguments

# Get all tool_use blocks with their inputs
[.content[] | select(.type == "tool_use") | {name, input}]

Filter streaming chunks (concatenate text)

# From a newline-delimited stream of delta events
# (Use with jq -s for slurp mode)
[.[] | select(.type == "content_block_delta") | .delta.text] | join("")

When to Use Online Playground vs CLI

Use the online playground when:

• Prototyping a new filter expression
• Debugging why a filter isn't working
• Sharing a jq snippet with a teammate (jqplay.org generates shareable URLs)
• You don't have jq installed locally
• You're on a machine where installing software is restricted

Use the command-line jq when:

• Processing files larger than a few MB
• Scripting (shell pipelines, CI/CD)
• Processing hundreds or thousands of JSON files
• You need the full flag set (--arg, --argjson, --rawfile, etc.)
• Real-time streaming from an API

Installing jq Locally

If you outgrow the online playgrounds:

# macOS
brew install jq

# Ubuntu/Debian
sudo apt install jq

# Windows (winget)
winget install jqlang.jq

# Direct download
# https://jqlang.github.io/jq/download/

Verify:

jq --version
# jq-1.7.1

Fixing Broken JSON Before Using jq

jq is strict about valid JSON. If your input has issues — trailing commas, single quotes, Python True/False booleans, comments — jq will reject it:

jq: parse error (Invalid numeric literal at line 1, column 23)

Before trying to filter with jq, repair the JSON:

1. Paste into AI JSON Medic — the 16-stage repair engine handles all common LLM output issues
2. Copy the repaired JSON
3. Run your jq filter on the valid output

This is especially common with LLM-generated JSON that has truncation, single quotes, or unescaped characters. Repair first, then filter.

jq vs JSONPath: Which to Use?

Both jq and JSONPath query JSON. The main differences:

For pure extraction from known structure (especially in browsers), JSONPath is simpler. For transformation, computation, and reshaping, jq is far more powerful.

AI JSON Medic includes a JSONPath tester for browser-native JSONPath queries — no installation, no WASM dependency.

Advanced jq Patterns

Recursive descent

# Find all values at any depth for key "error"
.. | objects | .error? // empty

Try-catch for optional fields

# Don't fail if field is missing
try .user.address.city catch "unknown"

Build from template

# Create new object with computed fields
{
  id: .id,
  full_name: "\(.first_name) \(.last_name)",
  is_admin: (.role == "admin"),
  item_count: (.items | length)
}

Multiple outputs to array

# Wrap exploded output back into array
[.users[] | select(.active) | .email]

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Frequently Asked Questions

Does jqplay.org store my JSON data?

Filter expressions in jqplay.org are sent to a server to run jq. If your JSON contains sensitive data (API keys, PII, credentials), use a WASM-based playground that runs locally, or install jq on your machine.

What version of jq do online playgrounds run?

jqplay.org runs jq 1.7. Most others run 1.6 or 1.7. Check the playground's documentation — jq 1.7 added getpath, setpath, delpaths, path, and env object support.

Can jq handle NDJSON (newline-delimited JSON)?

Yes — use jq -s (slurp) to read all newline-delimited JSON objects into a single array, then filter normally. Or use jq -c to output each result as compact JSON on its own line.

Why does jq output strings with quotes?

By default jq outputs valid JSON, so strings are quoted. Use jq -r (--raw-output) to strip quotes from string output. Useful when piping jq output to echo or other commands that don't want JSON-encoded strings.

Is there a jq formatter? jq . with no filter is the standard jq pretty-printer. Equivalent to jq --indent 4 . for 4-space indentation. For a full-featured online JSON formatter, AI JSON Medic's format tool offers live formatting with syntax highlighting. Can jq repair broken JSON?

No — jq requires valid JSON as input and will error on malformed data. For broken JSON (trailing commas, single quotes, missing brackets), use a repair tool first. AI JSON Medic repairs the JSON, then you can filter with jq.