{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"vat"},"result":{"entity_type":"calculator","id":"vat","calculator_id":"vat","canonical_url":"https://tttkmbb.com/finance/vat","name":"VAT Calculator","title":"VAT Calculator – Add or Remove Value-Added Tax between Net and Gross Prices","category":"finance","category_name":"Finance","tool_name":"calculate_vat","featured_mcp_tool":false,"description":"Adds VAT at a given rate to a net price, or removes it from a gross (VAT-inclusive) price, returning net, VAT and gross amounts.","use_when":"You need the VAT-inclusive price for an invoice, or the net price and VAT portion of a gross amount, at a known rate such as 20 % (UK), 19 % (Germany) or 21 % (Netherlands).","do_not_use_when":"You are dealing with US sales tax terminology (use sales-tax; the arithmetic is identical), or with multiple rates on one invoice (compute each line separately).","inputs":[{"name":"amount","label":"Amount","type":"number","required":true,"min":0,"max":1000000000,"description":"Net price (mode=add_vat) or gross VAT-inclusive price (mode=remove_vat).","example":100},{"name":"vat_rate_percent","label":"VAT rate","type":"number","unit":"%","required":false,"default":20,"min":0,"max":100,"description":"VAT rate in percent; standard rates in the EU range from 17 % to 27 %.","example":20},{"name":"mode","label":"Mode","type":"enum","required":false,"default":"add_vat","values":[{"value":"add_vat","label":"Add VAT to a net price","aliases":["add","net_to_gross","exclusive"]},{"value":"remove_vat","label":"Remove VAT from a gross price","aliases":["remove","extract","gross_to_net","inclusive","reverse"]}],"description":"Whether amount is net (add) or gross (remove).","example":"add_vat"}],"outputs":[{"name":"net_amount","label":"Net (excluding VAT)","type":"number","decimals":2,"description":"Price before VAT."},{"name":"vat_amount","label":"VAT","type":"number","decimals":2,"description":"net_amount × rate."},{"name":"gross_amount","label":"Gross (including VAT)","type":"number","decimals":2,"description":"net_amount + vat_amount."},{"name":"vat_fraction_of_gross","label":"VAT fraction of gross","type":"number","decimals":6,"description":"rate / (100 + rate), e.g. 1/6 at 20 %: multiply a gross price by this to get the VAT."}],"input_schema":{"type":"object","properties":{"amount":{"description":"Net price (mode=add_vat) or gross VAT-inclusive price (mode=remove_vat).","type":"number","minimum":0,"maximum":1000000000,"examples":[100]},"vat_rate_percent":{"description":"VAT rate in percent; standard rates in the EU range from 17 % to 27 %. Unit: %.","type":"number","minimum":0,"maximum":100,"default":20,"examples":[20],"x-unit":"%"},"mode":{"description":"Whether amount is net (add) or gross (remove).","type":"string","enum":["add_vat","remove_vat"],"default":"add_vat","examples":["add_vat"]}},"additionalProperties":false,"required":["amount"]},"output_schema":{"type":"object","properties":{"net_amount":{"description":"Price before VAT.","type":"number"},"vat_amount":{"description":"net_amount × rate.","type":"number"},"gross_amount":{"description":"net_amount + vat_amount.","type":"number"},"vat_fraction_of_gross":{"description":"rate / (100 + rate), e.g. 1/6 at 20 %: multiply a gross price by this to get the VAT.","type":"number"}}},"formula":"add_vat: vat = amount × rate/100, gross = amount + vat. remove_vat: net = amount / (1 + rate/100), vat = amount − net","sources":[{"name":"Wikipedia – Value-added tax","url":"https://en.wikipedia.org/wiki/Value-added_tax","type":"reference","retrieved_at":"2026-09-23"},{"name":"GOV.UK – VAT rates","url":"https://www.gov.uk/vat-rates","type":"government","retrieved_at":"2026-09-23"},{"name":"European Commission – VAT (rates and rules in the EU)","url":"https://taxation-customs.ec.europa.eu/taxation/vat_en","type":"government","retrieved_at":"2026-09-23"}],"freshness":{"type":"static","max_age_seconds":null,"note":"Deterministic formula with fixed constants; results never go stale. Inputs supplied by the caller determine the output."},"examples":[{"name":"100 net plus 20 % VAT","inputs":{"amount":100,"vat_rate_percent":20,"mode":"add_vat"},"expected":{"net_amount":100,"vat_amount":20,"gross_amount":120,"vat_fraction_of_gross":0.166667},"url":"https://tttkmbb.com/api/v1/calculate/vat?amount=100&vat_rate_percent=20&mode=add_vat"},{"name":"119 gross, remove 19 % VAT","inputs":{"amount":119,"vat_rate_percent":19,"mode":"remove_vat"},"expected":{"net_amount":100,"vat_amount":19,"gross_amount":119},"url":"https://tttkmbb.com/api/v1/calculate/vat?amount=119&vat_rate_percent=19&mode=remove_vat"}],"faq":[{"q":"What is the VAT fraction?","a":"The share of a gross price that is VAT: rate / (100 + rate). At 20 % it is 1/6, so the VAT in a 120 gross price is 20, not 24."},{"q":"Which rate applies?","a":"Standard rates apply to most goods; reduced or zero rates apply to items such as food, books or children's clothing depending on the country. Check the national tax authority's list."}],"tags":["vat calculator","add vat","remove vat","net to gross","value added tax","reverse vat"],"related":[{"calculator_id":"sales-tax","reason":"US-style sales tax with the same arithmetic."},{"calculator_id":"margin-markup","reason":"Set a net selling price from cost before adding VAT."}],"links":{"html":"https://tttkmbb.com/finance/vat","markdown":"https://tttkmbb.com/finance/vat.md","json":"https://tttkmbb.com/finance/vat.json","api":"https://tttkmbb.com/api/v1/calculate/vat","schema":"https://tttkmbb.com/api/v1/calculators/vat","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-23"},"timestamp":"2026-09-23T23:24:36Z"}