Forge Json

Format JSON Online

Paste JSON to format, clean, trim, sort keys, and prepare the document before validation, diffing, conversion, or pipeline automation.

Paste your JSON → Get results instantly (no signup)

⚡ Instant resultsNo signupRuns in your browser
Try examples:

→ remove noisy values and remove nulls and empties.

{
"name": "Alice",
"bio": "",
"age": 30,
"address": null,
"tags": [],
"meta": {}
}
Output✓
1{
2  "name": "Alice",
3  "age": 30
4}

Love the result?

Use this exact pipeline in your app, backend, or LLM workflow.

No setup needed. Works with curl, Node, Python.

Uses example data. For edited input, copy from the playground.

Read integration guide

Works with:

  • Pretty-printing JSON
  • Cleaning API responses
  • Preparing JSON before diffing
  • Formatter and validator workflows

Example: input → output

Format JSON online

A JSON formatter makes JSON easier to read before you validate, compare, transform, or export it. Paste a compact or messy payload into the tool and run the formatter to clean whitespace, trim noisy values, sort keys, and produce a more predictable document for downstream work.

This page uses the same engine as Clean JSON, but it is written for users searching for a JSON formatter. The goal is simple: make the input readable and stable enough for the next step. If the JSON is invalid, validate it first. If the JSON is valid but hard to scan, formatting and cleanup can make differences easier to review.

When to use a JSON formatter

Use a formatter before sharing an API example, saving a config file, comparing two versions, or exporting data. Formatted JSON helps developers spot nested fields, missing objects, inconsistent values, and fields that should be removed before a payload goes into production.

Formatting is especially useful before a JSON Diff Tool. If one payload is minified and the other is pretty-printed, text comparison becomes noisy. Formatting and cleanup reduce that noise so the structured diff focuses on changed values, added fields, and removed keys.

JSON formatter vs validator

A JSON validator checks whether the document is valid enough to parse. A formatter changes the presentation of valid JSON and can optionally clean common noise. Use JSON Validator first when you suspect syntax errors, then use the formatter to prepare the valid document for review.

If you are comparing two payloads, format both sides using the same cleanup rules. Do not sort keys, trim values, or remove fields on only one side unless that transformation is what you are intentionally testing.

Related tools

Read more on the blog

Advanced usage (optional)

Clean Values

v1.0.0
Cleanup
objectarraydestructive

Description

Clean Values

Remove nulls, empty strings, empty collections, default values, and duplicates from JSON data. Optionally trim whitespace and sort keys. A comprehensive cleanup utility for normalizing messy data.

Operations

Each cleanup operation can be toggled independently. Enable multiple operations to clean data in a single pass.

Remove null values

Delete object keys that have null values at any depth.

Remove empty strings

Delete object keys that have empty string "" values.

Remove empty collections

Delete empty objects {} and empty arrays [].

Remove default values

Delete falsy defaults — 0 and false. Useful for stripping placeholder values.

Remove duplicates

Remove duplicate items in arrays. Compares both primitive values and full objects (deep equality).

Trim whitespace

Trim leading and trailing whitespace from all string values throughout the document.

Sort object keys

Sort object keys alphabetically at all levels.

Configuration

FieldTypeDefaultDescription
Apply topath-picker[]Scope operations to specific paths only (empty = apply everywhere)
Remove null valuesbooleantrueRemove object keys with null values
Remove empty stringsbooleantrueRemove object keys with empty string values
Trim whitespacebooleantrueTrim leading/trailing whitespace from strings
Remove empty collectionsbooleanfalseRemove empty objects {} and arrays []
Remove duplicatesbooleanfalseRemove duplicate items in arrays
Remove default valuesbooleanfalseRemove falsy defaults (0, false)
Sort object keysbooleantrueSort object keys alphabetically

Use Cases

API Response Cleanup

  • Strip null fields from API responses before displaying
  • Remove internal metadata fields (__v, _id) with empty values
  • Trim whitespace from user-submitted form data

Data Normalization

  • Deduplicate records imported from multiple sources
  • Sort keys for consistent ordering across objects
  • Remove placeholder defaults before exporting

Configuration

NameTypeDefaultDescription
Apply topath-picker[]Scope operations to specific paths only (empty = apply everywhere)
Remove null valuesbooleantrueRemove object keys that have null values
Remove empty stringsbooleantrueRemove object keys that have empty string values
Trim whitespacebooleantrueTrim leading and trailing whitespace from all string values
Remove empty collectionsbooleanfalseRemove empty objects {} and empty arrays []
Remove duplicatesbooleanfalseRemove duplicate items in arrays (primitives and objects)
Remove default valuesbooleanfalseRemove falsy defaults (0, false)
Sort object keysbooleantrueSort object keys alphabetically

Examples

AI Prompt
Clean up this JSON and remove noisy values and remove nulls and empties.
{
"name": "Alice",
"bio": "",
"age": 30,
"address": null,
"tags": [],
"meta": {}
}
Output✓
1{
2  "name": "Alice",
3  "age": 30
4}
Config
Remove null values
ON
Remove empty strings
ON
Trim whitespace
OFF
Remove empty collections
ON
Remove duplicates
OFF
Remove default values
OFF
Sort object keys
OFF

API Usage

POST /api/v1/utilities/cleanup.clean-json
Example:
curl -X POST https://your-domain.com/api/v1/utilities/cleanup.clean-json \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"inputs":{"primary":{"name":"Alice","bio":"","age":30,"address":null,"tags":[],"meta":{}}},"config":{"removeNulls":true,"removeEmptyStrings":true,"removeEmptyCollections":true,"removeDefaults":false,"removeDuplicates":false,"trimStrings":false,"sortKeys":false}}'
Response
1{
2  "name": "Alice",
3  "age": 30
4}