Skip to main content
appkiro.com

JSON Formatter Online: Beautify, Minify and Validate

Clean up, compress or validate JSON without switching tools. Choose indentation, sort keys, escape non-ASCII characters and inspect syntax errors before you copy or download the result.

Read the full guide

Direct answer

A JSON formatter turns compact or inconsistent JSON into readable, consistently indented text. AppKiro also minifies valid JSON and checks strict RFC 8259 syntax; comments and trailing commas remain invalid.

Paste your JSON, choose the output mode and copy a clean result.

Valid JSON

Input JSON

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
324 Input chars · 16 Output lines

Output — Beautified

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
383 Output chars · 28 Output lines

Options

Tip: drag and drop a .json file, or paste from clipboard.

Statistics

324

Input chars

383

Output chars

28

Output lines

4

Max depth

12

Object keys

2

Arrays

+18.21%

Size change

Quick Actions

100% private — runs in your browser

Your JSON is parsed, formatted, and validated locally. Nothing is uploaded to any server.

JSONJSONLRFC 8259

How to use it

  1. Paste JSON or drag a .json file into the input editor.
  2. Choose Beautify, Minify or Validate, then set indentation, key sorting, Unicode escaping and the final newline.
  3. Review the formatted output and statistics, then copy or download the JSON.

Key features and settings

  • Beautify with 2 spaces, 4 spaces or Tab indentation.
  • Minify by removing nonessential whitespace while preserving JSON values.
  • Validate strict JSON and report a line/column location for syntax errors.
  • Sort object keys, escape non-ASCII characters and compare output size/depth statistics.

Supported input and output

Input: JSON text, .json. Output: formatted or minified JSON text, .json.

Use cases

  • Review API responses and webhook payloads.
  • Normalize fixtures or configuration files before committing them.
  • Reduce payload size for testing or quickly locate malformed JSON.

Which workflow should you choose?

Use JSON Formatter Online for: Beautify with 2 spaces, 4 spaces or Tab indentation. Use JSON to JSON Schema Generator for: Draft selection from legacy drafts through 2020-12 in the current UI.

Privacy and data path

In the current paste/upload workflow, the content is processed in the browser.

Limits and troubleshooting

  • Comments, single quotes and trailing commas belong to JSON5/JSONC—not strict JSON—so remove them before validating.
  • There is no universal size promise; large-input performance depends on browser memory and device capability.

FAQ

Does the validator support JSON5 or JSONC?

No. The current validator targets strict JSON. Comments, single-quoted strings and trailing commas produce errors.

Is my data uploaded to a server?

In the current paste/upload workflow, the content is processed in the browser.

What are the file or data limits?

There is no universal size promise; large-input performance depends on browser memory and device capability.

Does it work on mobile?

The page is web-based and may work in a modern mobile browser, but file-picker behavior, memory and cross-device compatibility are not verified for every device. Use a desktop browser for large or complex inputs.

Which workflow should you choose?

Use JSON Formatter Online for: Beautify with 2 spaces, 4 spaces or Tab indentation. Use JSON to JSON Schema Generator for: Draft selection from legacy drafts through 2020-12 in the current UI.

Related tools

Paste your JSON, choose the output mode and copy a clean result.