jq subset
This playground runs a jq subset in your browser. It is not the full jq command-line tool.
Supported: field access, pipes, map, select, sort_by, group_by, keys, length, and object construction.
Not supported: reduce, try, foreach, recursive descent (..), and custom functions.
jq-subset expression
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JSON Input
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Result
Enter JSON and a jq expression to see results
Supported jq-subset operations
Data Access
.field- Field access.[n]- Array index.[]- Iterate array/object.[n:m]- Array slice.a.b- Nested field access
Array Operations
map()- Transform each itemselect()- Filter by conditionsort / sort_by()- Sort arrayfirst / last- Get first/last itemflatten- Flatten nested arrays
Aggregation
length- Get lengthadd- Sum/concatenatemin / max- Find min/maxunique- Remove duplicatesgroup_by()- Group by field
Object & Type
keys / values- Get keys/valuestype- Get data typeto_entries- Object to entrieshas() / contains()- Check existencedel()- Delete field
How to Use the JQ Playground
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Paste or load your JSON data
Paste raw JSON into the input panel or click Load Example to start with sample data. You can also drag and drop a.json file directly into the editor. The playground accepts any valid JSON structure including objects, arrays, and nested data. - 2
Write a jq-subset expression
Type a supported filter in the expression field at the top. Start with simple accessors like .name or .users[] and build pipelines such as .items | map(select(.price > 10)) | sort_by(.name). reduce, try, and foreach are not supported. Use the cheat sheet for the subset this page runs. - 3
Review the output
Results appear instantly in the output panel as you type. The playground highlights syntax errors and shows formatted JSON output. If your expression returns multiple values, each result is displayed on its own line for easy inspection. - 4
Copy or download the result
Click Copy to place the output on your clipboard, or use Download JSON to save the transformed data as a file. Your query history is preserved so you can revisit and refine previous expressions without retyping them.
Common Use Cases
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Filtering API Responses
Extract specific fields from large REST or GraphQL API responses. Use select() and map() to pull only the data you need, such as user emails, product prices, or error messages buried in deeply nested JSON payloads.
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Transforming Log Files
Parse JSON-formatted server logs to isolate timestamps, error codes, and request paths. Chain jq filters to group errors by status code, count occurrences, or flatten nested log entries into a flat CSV-friendly structure.
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Preparing Data for Visualization
Reshape raw JSON datasets into the exact format your charting library or spreadsheet expects. Use group_by, unique, and object construction to aggregate values, rename keys, and restructure arrays before exporting.
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Learning and Prototyping jq Queries
Experiment with jq syntax before embedding expressions in shell scripts, CI pipelines, or backend code. The instant feedback loop and built-in examples make this playground ideal for beginners and experienced developers alike.
Why use our JQ Playground?
Test common jq-subset filters in real time without installing anything. Paste your JSON, write a filter, and see results instantly. This playground supports field access, array operations, map, select, sort_by, and group_by. It does not run reduce, try, or foreach. Built-in examples and a cheat sheet cover the supported subset. All processing runs locally in your browser.
The JQ Playground is a browser-based environment for testing a jq subset against live JSON data. jq is a command-line JSON processor often called "sed for JSON". This page does not run full jq. It supports field access, pipes, map, select, sort_by, and group_by. It does not run reduce, try, or foreach.
Use it to extract fields from a REST API response, reshape a dataset for a JSON to Chart visualization, or flatten objects before a JSON to CSV export. Built-in examples cover the supported subset. For full jq, install the jq command-line tool.
All processing runs in your browser. Pair it with the JSON Formatter, the JSON Path Finder, or the JSON Visualizer.
How It Compares
JSONPath selects nodes from a JSON document. Full jq can also transform and aggregate data, including with reduce and user-defined functions. This playground is a jq subset: it runs pipes, map, and select, and it does not run reduce, try, or foreach.
For everyday API field extraction, the subset is enough. For recursive descent, try/catch, or custom functions, use the jq CLI or a JavaScript script.
Tips for Writing Better jq Filters
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Start with the identity filter (.) to inspect the full input structure before writing complex queries. 2
Use the pipe operator (|) to build queries incrementally — add one operation at a time and verify the output at each step. 3
Wrap select() inside map() when filtering arrays:.items | map(select(.active == true)) returns an array rather than individual elements. 4
Construct new objects with {key:.field} syntax to reshape data and pick only the fields you need from each record. 5
Combine sort_by, group_by, and unique to aggregate data without writing loops — jq handles iteration implicitly. Frequently Asked Questions
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What is jq and what is it used for?
jq is a lightweight command-line JSON processor, often described as "sed for JSON." This playground runs a jq subset in your browser so you can test common filters without installing the jq CLI. It is not a full jq implementation.
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How do I filter JSON arrays with jq?
Use the select() function to filter array elements. For example.users | select(.age > 25) returns users older than 25. You can combine multiple conditions:.items | select(.price > 10 and.active == true). Use map(select(.)) when you need the output as an array.
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Does this jq playground require a signup?
No. This JQ Playground is available with no usage limits. All processing happens in your browser — your JSON data is never sent to any server. There's no account required, and no restrictions on the size of JSON you can process.
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How do I pipe multiple jq operations together?
Use the pipe character (|) to chain operations sequentially. For example:.users | select(.active) | map(.name) first gets the users array, then filters to active users only, then extracts just the name field from each. Each pipe passes its output as input to the next operation.
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What is the difference between jq and JSONPath?
JSONPath selects nodes from JSON. Full jq can also transform, aggregate, and construct new JSON. This playground is a jq subset: it runs pipes, map, and select, but it does not run reduce, try, or foreach. Use the jq CLI for those.
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Does this support the full jq specification?
No. This page runs a jq subset. Supported operations include field access, array indexing and slicing, pipes, map, select, sort_by, group_by, unique, flatten, keys, values, and object construction. It does not run reduce, try, foreach, recursive descent (..), or custom functions. Use the jq command-line tool for those.
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Can I use jq without installing it?
You can try a jq subset here without installing anything. Paste JSON, write a supported filter, and see results in the browser. For full jq, including reduce, try, and foreach, install the jq CLI.
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How do I select specific fields from JSON objects?
Use object construction syntax:.users | map({name, email}) extracts only the name and email fields. To rename fields, use: map({full_name:.name, mail:.email}). For a single object, just use {name:.name, age:.age}.
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How do I group and aggregate data with jq?
Use group_by(.field) to group array elements by a shared value, then pipe the result through map to aggregate each group. For example, [.orders[] | group_by(.status)] groups orders by status. To count each group, add | map({status:.[0].status, count: length}). You can also sum values with map(map(.amount) | add) after grouping.
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How does jq compare to writing JavaScript for JSON processing?
jq expressions are typically 5-10x shorter than equivalent JavaScript. A pipeline like.users | map(select(.active)) | sort_by(.name) | map(.email) would require multiple lines of JS with filter(), sort(), and map() calls. jq's advantage is conciseness and its pipe-oriented design. JavaScript's advantage is broader ecosystem support and easier debugging for complex logic.