# Energy

- Human page: https://happytails.ai/en/unit-converters/energy/
- Markdown: https://happytails.ai/en/unit-converters/energy.md
- Structured JSON: https://happytails.ai/agents/en/unit-converters/energy/index.json
- Visibility: public

## Tool capabilities

| Property | Value |
| --- | --- |
| Tool ID | `energy` |
| Category | unit-converters |
| 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/energy/run |
| Browser-agent interface | run_current_tool |

### Inputs and settings

No free-text input is required. Use the file inputs and/or settings below.

| Setting | Meaning | Control type | Default | Constraints |
| --- | --- | --- | --- | --- |
| `value` | Value | number | 1 |  |
| `from` | From | select | "J" | Allowed: J, kJ, cal, kcal, Wh, kWh |
| `to` | To | select | "kJ" | Allowed: J, kJ, cal, kcal, Wh, kWh |

### 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/energy/run
Content-Type: application/json
```

[Detailed operation reference](https://happytails.ai/en/api/tools/energy.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": {
        "value": {
          "type": "number",
          "description": "Value",
          "default": 1.0
        },
        "from": {
          "type": "string",
          "description": "From",
          "default": "J",
          "enum": [
            "J",
            "kJ",
            "cal",
            "kcal",
            "Wh",
            "kWh"
          ]
        },
        "to": {
          "type": "string",
          "description": "To",
          "default": "kJ",
          "enum": [
            "J",
            "kJ",
            "cal",
            "kcal",
            "Wh",
            "kWh"
          ]
        }
      }
    }
  }
}
```

#### 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 `run_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

Clear joule/calorie/kWh definitions and precision.

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

### Complete machine-readable capability record

```json
{
  "id": "energy",
  "category": "unit-converters",
  "built": true,
  "requirements": "Clear joule/calorie/kWh definitions and precision.",
  "implementation": {
    "fields": [
      {
        "key": "value",
        "label": "Value",
        "value": 1,
        "type": "number"
      },
      {
        "key": "from",
        "label": "From",
        "value": "J",
        "type": "select",
        "values": [
          "J",
          "kJ",
          "cal",
          "kcal",
          "Wh",
          "kWh"
        ],
        "labels": {
          "m": "Meters (m)",
          "km": "Kilometers (km)",
          "cm": "Centimeters (cm)",
          "mm": "Millimeters (mm)",
          "in": "Inches (in)",
          "ft": "Feet (ft)",
          "yd": "Yards (yd)",
          "mi": "Miles (mi)",
          "kg": "Kilograms (kg)",
          "g": "Grams (g)",
          "mg": "Milligrams (mg)",
          "lb": "Pounds (lb)",
          "oz": "Ounces (oz)",
          "tonne": "Metric tonnes",
          "m²": "Square meters (m²)",
          "km²": "Square kilometers (km²)",
          "cm²": "Square centimeters (cm²)",
          "ft²": "Square feet (ft²)",
          "in²": "Square inches (in²)",
          "L": "Liters (L)",
          "mL": "Milliliters (mL)",
          "m³": "Cubic meters (m³)",
          "US fl oz": "US fluid ounces",
          "m/s": "Meters per second (m/s)",
          "km/h": "Kilometers per hour (km/h)",
          "mph": "Miles per hour (mph)",
          "knot": "Knots",
          "kB": "Kilobytes (kB, 1,000 bytes)",
          "MB": "Megabytes (MB, 1,000,000 bytes)",
          "GB": "Gigabytes (GB, decimal)",
          "TB": "Terabytes (TB, decimal)",
          "KiB": "Kibibytes (KiB, 1,024 bytes)",
          "MiB": "Mebibytes (MiB, 1,048,576 bytes)",
          "GiB": "Gibibytes (GiB, binary)",
          "TiB": "Tebibytes (TiB, binary)",
          "Pa": "Pascals (Pa)",
          "kPa": "Kilopascals (kPa)",
          "atm": "Standard atmospheres (atm)",
          "psi": "Pounds per square inch (psi)",
          "J": "Joules (J)",
          "kJ": "Kilojoules (kJ)",
          "cal": "Thermochemical calories (cal)",
          "kcal": "Kilocalories (kcal)",
          "Wh": "Watt-hours (Wh)",
          "kWh": "Kilowatt-hours (kWh)",
          "W": "Watts (W)",
          "kW": "Kilowatts (kW)",
          "MW": "Megawatts (MW)",
          "hp": "Mechanical horsepower (hp)"
        }
      },
      {
        "key": "to",
        "label": "To",
        "value": "kJ",
        "type": "select",
        "values": [
          "J",
          "kJ",
          "cal",
          "kcal",
          "Wh",
          "kWh"
        ],
        "labels": {
          "m": "Meters (m)",
          "km": "Kilometers (km)",
          "cm": "Centimeters (cm)",
          "mm": "Millimeters (mm)",
          "in": "Inches (in)",
          "ft": "Feet (ft)",
          "yd": "Yards (yd)",
          "mi": "Miles (mi)",
          "kg": "Kilograms (kg)",
          "g": "Grams (g)",
          "mg": "Milligrams (mg)",
          "lb": "Pounds (lb)",
          "oz": "Ounces (oz)",
          "tonne": "Metric tonnes",
          "m²": "Square meters (m²)",
          "km²": "Square kilometers (km²)",
          "cm²": "Square centimeters (cm²)",
          "ft²": "Square feet (ft²)",
          "in²": "Square inches (in²)",
          "L": "Liters (L)",
          "mL": "Milliliters (mL)",
          "m³": "Cubic meters (m³)",
          "US fl oz": "US fluid ounces",
          "m/s": "Meters per second (m/s)",
          "km/h": "Kilometers per hour (km/h)",
          "mph": "Miles per hour (mph)",
          "knot": "Knots",
          "kB": "Kilobytes (kB, 1,000 bytes)",
          "MB": "Megabytes (MB, 1,000,000 bytes)",
          "GB": "Gigabytes (GB, decimal)",
          "TB": "Terabytes (TB, decimal)",
          "KiB": "Kibibytes (KiB, 1,024 bytes)",
          "MiB": "Mebibytes (MiB, 1,048,576 bytes)",
          "GiB": "Gibibytes (GiB, binary)",
          "TiB": "Tebibytes (TiB, binary)",
          "Pa": "Pascals (Pa)",
          "kPa": "Kilopascals (kPa)",
          "atm": "Standard atmospheres (atm)",
          "psi": "Pounds per square inch (psi)",
          "J": "Joules (J)",
          "kJ": "Kilojoules (kJ)",
          "cal": "Thermochemical calories (cal)",
          "kcal": "Kilocalories (kcal)",
          "Wh": "Watt-hours (Wh)",
          "kWh": "Kilowatt-hours (kWh)",
          "W": "Watts (W)",
          "kW": "Kilowatts (kW)",
          "MW": "Megawatts (MW)",
          "hp": "Mechanical horsepower (hp)"
        }
      }
    ],
    "input": false,
    "note": "",
    "live": true,
    "presentation": "metrics",
    "experience": {
      "automatic": true,
      "single": false,
      "label": "Your text",
      "placeholder": "Type or paste your input…",
      "help": "Change the input or settings to update your result. Results update as you type. Up to 1,000,000 characters.",
      "action": null
    },
    "mode": "automatic",
    "interactive": false
  },
  "execution": "POST /api/v1/tools/energy/run",
  "api": {
    "id": "energy",
    "name": "Energy",
    "category": "unit-converters",
    "description": "Convert between joules, calories, watt-hours, and kilowatt-hours.",
    "notes": "",
    "human_path": "/en/unit-converters/energy/",
    "method": "POST",
    "endpoint": "/api/v1/tools/energy/run",
    "schema_url": "/api/v1/tools/energy",
    "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": {
            "value": {
              "type": "number",
              "description": "Value",
              "default": 1.0
            },
            "from": {
              "type": "string",
              "description": "From",
              "default": "J",
              "enum": [
                "J",
                "kJ",
                "cal",
                "kcal",
                "Wh",
                "kWh"
              ]
            },
            "to": {
              "type": "string",
              "description": "To",
              "default": "kJ",
              "enum": [
                "J",
                "kJ",
                "cal",
                "kcal",
                "Wh",
                "kWh"
              ]
            }
          }
        }
      }
    },
    "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": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}
```

## Page guide

Convert between joules, calories, watt-hours, and kilowatt-hours.

## How to use Energy

1. Enter the values you want to calculate and choose the relevant units or settings.
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.

## What to expect

Convert between joules, calories, watt-hours, and kilowatt-hours. Enter a value and choose the source and destination units. Your result updates automatically. The calculation uses the selected units; displayed digits do not improve the accuracy of your original measurement.

### Try a small example

```
3,600,000 J = 1 kWh
```

## Useful next steps

- [Ohms law](https://happytails.ai/en/maker-tools/ohms-law/): Calculate current and power from voltage and resistance. ([Markdown](https://happytails.ai/en/maker-tools/ohms-law.md))

- [Power](https://happytails.ai/en/unit-converters/power/): Convert between watts, kilowatts, megawatts, and horsepower. ([Markdown](https://happytails.ai/en/unit-converters/power.md))

- [Scientific notation](https://happytails.ai/en/calculators/scientific-notation/): Write a number in scientific notation. ([Markdown](https://happytails.ai/en/calculators/scientific-notation.md))