{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"percentage"},"result":{"entity_type":"calculator","id":"percentage","calculator_id":"percentage","canonical_url":"https://tttkmbb.com/math/percentage","name":"Percentage Calculator","title":"Percentage Calculator – X% of Y, X Is What Percent of Y, X Is Y% of What","category":"math","category_name":"Math","tool_name":"calculate_percentage","featured_mcp_tool":true,"description":"Solves the three basic percentage questions (a percentage of a number, what percentage one number is of another, and the whole behind a known part and percentage). Always returns the part, the whole and the percent.","use_when":"You need a percentage of a value, the percentage one value represents of another, or the base value that a part and its percentage imply.","do_not_use_when":"You need the percentage change between two values (use percentage-change), a price after a percentage discount (use discount) or a tax amount (use sales-tax).","inputs":[{"name":"mode","label":"Question","type":"enum","required":false,"default":"percent_of","values":[{"value":"percent_of","label":"What is x% of y?","aliases":["of","percent of"]},{"value":"is_what_percent","label":"x is what percent of y?","aliases":["what percent","percent"]},{"value":"percent_of_what","label":"x is y% of what?","aliases":["of what","whole","base"]}],"description":"Which percentage question to solve; x and y take the meaning shown in the label of the chosen mode.","example":"percent_of"},{"name":"x","label":"x","type":"number","required":true,"description":"First number: the percent (percent_of) or the part (is_what_percent, percent_of_what). Percents are plain numbers, 15 means 15%.","example":15},{"name":"y","label":"y","type":"number","required":true,"description":"Second number: the whole (percent_of, is_what_percent) or the percent (percent_of_what).","example":240}],"outputs":[{"name":"result","label":"Result","type":"number","decimals":4,"description":"The unknown quantity: the part (percent_of), the percent in % (is_what_percent) or the whole (percent_of_what)."},{"name":"sentence","label":"In words","type":"string","decimals":4,"description":"The solved statement, e.g. '15% of 240 is 36.'"},{"name":"part","label":"Part","type":"number","decimals":4,"description":"The part: percent × whole / 100."},{"name":"whole","label":"Whole","type":"number","decimals":4,"description":"The base value that corresponds to 100%."},{"name":"percent","label":"Percent","type":"number","unit":"%","decimals":4,"description":"The percentage: part / whole × 100."}],"input_schema":{"type":"object","properties":{"mode":{"description":"Which percentage question to solve; x and y take the meaning shown in the label of the chosen mode.","type":"string","enum":["percent_of","is_what_percent","percent_of_what"],"default":"percent_of","examples":["percent_of"]},"x":{"description":"First number: the percent (percent_of) or the part (is_what_percent, percent_of_what). 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Inputs supplied by the caller determine the output."},"examples":[{"name":"What is 15% of 240?","inputs":{"mode":"percent_of","x":15,"y":240},"expected":{"result":36,"part":36,"whole":240,"percent":15,"sentence":"15% of 240 is 36."},"url":"https://tttkmbb.com/api/v1/calculate/percentage?mode=percent_of&x=15&y=240"},{"name":"30 is what percent of 120?","inputs":{"mode":"is_what_percent","x":30,"y":120},"expected":{"result":25,"part":30,"whole":120,"percent":25,"sentence":"30 is 25% of 120."},"url":"https://tttkmbb.com/api/v1/calculate/percentage?mode=is_what_percent&x=30&y=120"}],"faq":[{"q":"Do I enter 15 or 0.15 for 15%?","a":"Enter 15. Percentages are plain percent numbers everywhere on this site; the calculator divides by 100 internally."},{"q":"How do I find the whole from a part?","a":"Use mode percent_of_what: '36 is 15% of what?' gives x = 36, y = 15 and returns 240."},{"q":"What is the difference between percent and percentage points?","a":"Going from 10% to 15% is a rise of 5 percentage points but a 50% relative increase. This calculator handles plain percent arithmetic; use percentage-change for relative changes."}],"tags":["percentage","percent of","what percent","percent calculator","part whole percent"],"related":[{"calculator_id":"percentage-change","reason":"Percentage increase or decrease between two values."},{"calculator_id":"discount","reason":"Price after a percentage discount."},{"calculator_id":"fraction-simplifier","reason":"Express the same part/whole relationship as a reduced fraction."}],"links":{"html":"https://tttkmbb.com/math/percentage","markdown":"https://tttkmbb.com/math/percentage.md","json":"https://tttkmbb.com/math/percentage.json","api":"https://tttkmbb.com/api/v1/calculate/percentage","schema":"https://tttkmbb.com/api/v1/calculators/percentage","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-23"},"timestamp":"2026-09-23T23:23:14Z"}