{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"electricity-cost"},"result":{"entity_type":"calculator","id":"electricity-cost","calculator_id":"electricity-cost","canonical_url":"https://tttkmbb.com/everyday/electricity-cost","name":"Electricity Cost Calculator","title":"Electricity Cost Calculator – Appliance kWh and Running Cost per Day, Month and Year","category":"everyday","category_name":"Everyday Life","tool_name":"calculate_electricity_cost","featured_mcp_tool":false,"description":"Converts an appliance's power draw and daily usage into kilowatt-hours and the running cost per day, over a chosen number of days, per 30-day month and per 365-day year, using the US DOE energy-use formula.","use_when":"You want to know what a heater, fridge, computer, light or EV charger costs to run, or compare two appliances by energy cost.","do_not_use_when":"The appliance cycles or has standby modes with unknown duty cycle (use a measured kWh figure or plug-in meter), or you need to convert energy units (use energy).","inputs":[{"name":"power_watts","label":"Power","type":"number","unit":"W","required":true,"max":1000000,"exclusive_min":0,"description":"Power draw in watts while running (1 kW = 1000 W).","example":100},{"name":"hours_per_day","label":"Usage per day","type":"number","unit":"h/day","required":true,"min":0,"max":24,"description":"Hours the appliance actually draws that power each day.","example":5},{"name":"price_per_kwh","label":"Electricity price","type":"number","unit":"per kWh","required":true,"min":0,"max":100,"description":"Tariff per kilowatt-hour in your currency (from your bill).","example":0.15},{"name":"days","label":"Days in period","type":"integer","unit":"days","required":false,"default":30,"min":1,"max":3660,"description":"Length of the billing period to report.","example":30}],"outputs":[{"name":"kwh_per_day","label":"Energy per day","type":"number","unit":"kWh/day","decimals":3,"description":"power_watts × hours_per_day / 1000."},{"name":"cost_per_day","label":"Cost per day","type":"number","decimals":3,"description":"kwh_per_day × price_per_kwh."},{"name":"kwh_for_period","label":"Energy in period","type":"number","unit":"kWh","decimals":2,"description":"kwh_per_day × days."},{"name":"cost_for_period","label":"Cost in period","type":"number","decimals":2,"description":"cost_per_day × days."},{"name":"cost_per_month","label":"Cost per 30-day month","type":"number","decimals":2,"description":"cost_per_day × 30."},{"name":"cost_per_year","label":"Cost per year","type":"number","decimals":2,"description":"cost_per_day × 365."}],"input_schema":{"type":"object","properties":{"power_watts":{"description":"Power draw in watts while running (1 kW = 1000 W). Unit: W.","type":"number","maximum":1000000,"exclusiveMinimum":0,"examples":[100],"x-unit":"W"},"hours_per_day":{"description":"Hours the appliance actually draws that power each day. Unit: h/day.","type":"number","minimum":0,"maximum":24,"examples":[5],"x-unit":"h/day"},"price_per_kwh":{"description":"Tariff per kilowatt-hour in your currency (from your bill). Unit: per kWh.","type":"number","minimum":0,"maximum":100,"examples":[0.15],"x-unit":"per kWh"},"days":{"description":"Length of the billing period to report. Unit: days.","type":"integer","minimum":1,"maximum":3660,"default":30,"examples":[30],"x-unit":"days"}},"additionalProperties":false,"required":["power_watts","hours_per_day","price_per_kwh"]},"output_schema":{"type":"object","properties":{"kwh_per_day":{"description":"power_watts × hours_per_day / 1000. Unit: kWh/day.","type":"number","x-unit":"kWh/day"},"cost_per_day":{"description":"kwh_per_day × price_per_kwh.","type":"number"},"kwh_for_period":{"description":"kwh_per_day × days. Unit: kWh.","type":"number","x-unit":"kWh"},"cost_for_period":{"description":"cost_per_day × days.","type":"number"},"cost_per_month":{"description":"cost_per_day × 30.","type":"number"},"cost_per_year":{"description":"cost_per_day × 365.","type":"number"}}},"formula":"kWh/day = power_watts × hours_per_day / 1000; cost/day = kWh/day × price_per_kwh; period = × days; month = × 30; year = × 365","method":"Assumes constant power while running. Appliances with thermostats or motors (fridges, heaters, pumps) run only part of the time, so use their measured average draw or reduce hours_per_day accordingly.","sources":[{"name":"US DOE – Estimating Appliance and Home Electronic Energy Use","url":"https://www.energy.gov/energysaver/estimating-appliance-and-home-electronic-energy-use","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 W for 5 h/day at 0.15/kWh, 30 days","inputs":{"power_watts":100,"hours_per_day":5,"price_per_kwh":0.15,"days":30},"expected":{"kwh_per_day":0.5,"cost_per_day":0.075,"kwh_for_period":15,"cost_for_period":2.25,"cost_per_month":2.25,"cost_per_year":27.38},"url":"https://tttkmbb.com/api/v1/calculate/electricity-cost?power_watts=100&hours_per_day=5&price_per_kwh=0.15&days=30"},{"name":"1500 W heater 8 h/day at 0.30/kWh, 90 days","inputs":{"power_watts":1500,"hours_per_day":8,"price_per_kwh":0.3,"days":90},"expected":{"kwh_per_day":12,"cost_per_day":3.6,"kwh_for_period":1080,"cost_for_period":324,"cost_per_month":108,"cost_per_year":1314},"url":"https://tttkmbb.com/api/v1/calculate/electricity-cost?power_watts=1500&hours_per_day=8&price_per_kwh=0.3&days=90"}],"faq":[{"q":"Where do I find the wattage?","a":"On the appliance label or in its manual; if only amps are given, watts = volts × amps (e.g. 230 V × 0.5 A = 115 W). A plug-in power meter gives the real average draw."},{"q":"Does the price include taxes and standing charges?","a":"Use the all-in price per kWh from your bill (energy price plus per-kWh levies); fixed daily standing charges are not per-kWh and are not included."}],"tags":["electricity cost","kwh calculator","appliance running cost","energy bill","power consumption cost"],"related":[{"calculator_id":"electric-power","reason":"Compute watts from volts and amps or resistance."},{"calculator_id":"energy","reason":"Convert kWh to joules, BTU or calories."}],"links":{"html":"https://tttkmbb.com/everyday/electricity-cost","markdown":"https://tttkmbb.com/everyday/electricity-cost.md","json":"https://tttkmbb.com/everyday/electricity-cost.json","api":"https://tttkmbb.com/api/v1/calculate/electricity-cost","schema":"https://tttkmbb.com/api/v1/calculators/electricity-cost","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-23"},"timestamp":"2026-09-23T23:31:14Z"}