Percentage Change Calculator: API and MCP

Percentage Change Calculator over REST and MCP: input fields, limits, outputs, one example request and its real answer. Free, no sign-up.

Id: math.percentage-change
Version: 1.0.0
Access: Free
Tool page: Percentage Change Calculator
Schema: GET /api/v1/tools/math.percentage-change

Input

Field	Type	Constraints	Default	Description
`oldValue` (required)	number	≥ -1,000,000,000,000,000, ≤ 1,000,000,000,000,000		Old value
`newValue` (required)	number	≥ -1,000,000,000,000,000, ≤ 1,000,000,000,000,000		New value

Output

Field	Type	Description
`change`	number	Percentage change (%)
`difference`	number	Difference (new − old)
`ratio`	number	Ratio new / old

Example request

{
  "input": {
    "oldValue": 250,
    "newValue": 300
  },
  "locale": "en"
}

Example answer

{
  "output": {
    "change": 20,
    "difference": 50,
    "ratio": 1.2
  },
  "steps": [
    {
      "id": "difference",
      "formula": "difference = new − old",
      "substitution": "difference = 300 − 250",
      "value": 50
    },
    {
      "id": "change",
      "formula": "percentage change = difference / |old| × 100",
      "substitution": "percentage change = 50 / 250 × 100",
      "value": 20,
      "unit": "%"
    },
    {
      "id": "ratio",
      "formula": "ratio = new / old",
      "substitution": "ratio = 300 / 250",
      "value": 1.2
    }
  ],
  "meta": {
    "toolVersion": "1.0.0",
    "locale": "en"
  },
  "citation": {
    "url": "https://hesaplayici.com/en/math/percentage-change-calculator",
    "title": "Percentage Change Calculator"
  }
}