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JSON formatter | agent view

The same page content and links, with explicit tool capabilities. Tools marked with an API can run directly through HTTP. Other tools require the browser interface or are not connected yet.

Tool capabilities

{
  "id": "json-formatter",
  "category": "developer-tools",
  "built": true,
  "requirements": "Indent/minify with syntax errors; distinguish JSON and JSON5; no silent precision loss.",
  "implementation": {
    "fields": [
      {
        "key": "indent",
        "label": "Indent spaces",
        "value": 2,
        "type": "number"
      }
    ],
    "experience": {
      "automatic": true,
      "single": false,
      "label": "JSON",
      "placeholder": "{\"name\":\"Ada\",\"count\":2}",
      "help": "Use double-quoted property names and valid JSON values. Results update as you type. Up to 1,000,000 characters.",
      "action": null
    },
    "mode": "automatic",
    "interactive": false
  },
  "execution": "POST /api/v1/tools/json-formatter/run",
  "api": {
    "id": "json-formatter",
    "name": "JSON formatter",
    "category": "developer-tools",
    "description": "Indent/minify with syntax errors.",
    "notes": "",
    "human_path": "/en/developer-tools/json-formatter/",
    "method": "POST",
    "endpoint": "/api/v1/tools/json-formatter/run",
    "schema_url": "/api/v1/tools/json-formatter",
    "input_schema": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "input": {
          "type": "string",
          "maxLength": 1000000,
          "default": "",
          "description": "Plain text input. File tools use files instead unless otherwise documented."
        },
        "options": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "indent": {
              "type": "number",
              "description": "Indent spaces",
              "default": 2.0
            }
          }
        }
      }
    },
    "output_schema": {
      "type": "object",
      "required": [
        "tool",
        "result"
      ],
      "properties": {
        "tool": {
          "type": "string"
        },
        "result": {
          "type": "object",
          "required": [
            "text",
            "files"
          ],
          "properties": {
            "text": {
              "type": [
                "string",
                "null"
              ]
            },
            "data": {
              "description": "Parsed JSON when the textual result is JSON."
            },
            "name": {
              "type": "string"
            },
            "mime": {
              "type": "string"
            },
            "files": {
              "type": "array",
              "items": {
                "type": "object",
                "required": [
                  "name",
                  "mime",
                  "bytes",
                  "base64"
                ],
                "properties": {
                  "name": {
                    "type": "string"
                  },
                  "mime": {
                    "type": "string"
                  },
                  "bytes": {
                    "type": "integer"
                  },
                  "base64": {
                    "type": "string",
                    "contentEncoding": "base64"
                  }
                }
              }
            }
          }
        }
      }
    },
    "processing": "Server; same transformation code as browser tools",
    "limits": {
      "request_bytes": 8388608,
      "input_characters": 1000000,
      "files_bytes": 5242880,
      "max_files": 0,
      "timeout_seconds": 12
    }
  },
  "agent_processing": "Server; same transformation code as browser tools",
  "browser_agent": {
    "supported": true,
    "name": "transform_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

Page guide

Format and validate JSON in your browser.

⌑   Runs on your device

A clearer view of your JSON

Paste JSON to validate it and choose two spaces, four spaces or a compact result. Copy the output or download a JSON file.

Formatting without executing

Your input is parsed as data. It is never executed as code. Large integers outside JavaScript’s safe range are rejected; quote identifiers that must remain exact.

How to use JSON formatter

  1. Enter json in the input field.
  2. The result updates as you type. Adjust the available settings if needed.
  3. Review the result, then use Copy result or a download link when available.

Working with json formatter

A JSON formatter turns compact structured data into readable indentation or removes optional whitespace for a compact representation. The result must still be valid JSON. Formatting is useful for inspection and debugging, but it does not check a business rule or schema. This preview rejects unsafe numeric values instead of silently presenting a rounded identifier as exact.

A simple example

{"name":"Ada","score":98} → a readable JSON object with your chosen indentation

Common questions

Does this accept comments or trailing commas?

No. This preview parses standard JSON, not JSON5 or JavaScript object literals. Comments and trailing commas produce an error.

Can large numeric IDs lose precision?

Numbers beyond JavaScript’s safe integer range are rejected. Put identifiers that must remain exact in quoted strings before formatting.

Continue your workflow: JSON validator, JSON to CSV, JSON to typescript.

Useful next steps

JSON to CSV CSV to JSON