# JSON formatter

- Human page: https://happytails.ai/en/developer-tools/json-formatter/
- Markdown: https://happytails.ai/en/developer-tools/json-formatter.md
- Structured JSON: https://happytails.ai/agents/en/developer-tools/json-formatter/index.json
- Visibility: public

## Tool capabilities

| Property | Value |
| --- | --- |
| Tool ID | `json-formatter` |
| Category | developer-tools |
| Implementation | Registered implementation. Registration alone is not a production-quality guarantee. |
| Browser execution | Automatic updates after valid input or file selection. |
| Browser processing | Browser; see tool notes for network behavior. |
| HTTP API | /api/v1/tools/json-formatter/run |
| Browser-agent interface | transform_current_tool |

### Inputs and settings

Text input: JSON.

Example or placeholder shown in the interface (not a validated fixture):

```text
{"name":"Ada","count":2}
```

Use double-quoted property names and valid JSON values. Results update as you type. Up to 1,000,000 characters.

| Setting | Meaning | Control type | Default | Constraints |
| --- | --- | --- | --- | --- |
| `indent` | Indent spaces | number | 2 |  |

### HTTP contract

API calls process supplied data on the server. The website origin is `https://happytails.ai`. Server API hosting is not connected on the public website yet. Use your local server origin to test these requests.

```http
POST https://happytails.ai/api/v1/tools/json-formatter/run
Content-Type: application/json
```

[Detailed operation reference](https://happytails.ai/en/api/tools/json-formatter.md) · [Shared API guide](https://happytails.ai/en/api.md)

#### Limits

| Limit | Value |
| --- | --- |
| request_bytes | 8388608 |
| input_characters | 1000000 |
| files_bytes | 5242880 |
| max_files | 0 |
| timeout_seconds | 12 |

#### Complete input schema

```json
{
  "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
        }
      }
    }
  }
}
```

#### Complete output schema

```json
{
  "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"
              }
            }
          }
        }
      }
    }
  }
}
```

#### Error and retry handling

Failures return a non-200 status and `error.code` plus `error.message`. Correct invalid input before retrying; retry server-busy responses with bounded backoff. Returned files contain Base64 data, not persistent download URLs. Decode and inspect the output before treating conversion as successful. See the shared API guide for the complete status and timeout rules.

### Browser-agent workflow

1. Open the human page in a browser that supports WebMCP.
2. Discover the interface exposed by that page; use its actual schema.
3. Select files on the page first when the tool requires files.
4. Call `transform_current_tool` with valid input and settings.
5. Inspect the returned result or error and the displayed output. Retrieve files from the displayed download links.

Calls do not automatically copy or download results. Browser permissions still apply. Interface availability alone is not proof of successful execution.

### Planning specification

Indent/minify with syntax errors; distinguish JSON and JSON5; no silent precision loss.

This describes intended requirements. Use the implementation notes, interface schema and observed output to determine current support.

### Complete machine-readable capability record

```json
{
  "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](https://happytails.ai/en/developer-tools/json-validator/), [JSON to CSV](https://happytails.ai/en/data-tools/json-to-csv/), [JSON to typescript](https://happytails.ai/en/developer-tools/json-to-typescript/).

## Useful next steps

[JSON to CSV](https://happytails.ai/en/data-tools/json-to-csv/)

[CSV to JSON](https://happytails.ai/en/data-tools/csv-to-json/)