{"success":true,"version":"v1","request":{"tool":"get_calculator_schema","calculator_id":"burn-rate-runway"},"result":{"entity_type":"calculator","id":"burn-rate-runway","calculator_id":"burn-rate-runway","canonical_url":"https://tttkmbb.com/business/burn-rate-runway","name":"Burn Rate and Runway Calculator","title":"Burn Rate and Runway Calculator – Net Burn, Months of Runway and Zero-Cash Date","category":"business","category_name":"Business & Marketing","tool_name":"calculate_burn_rate_runway","featured_mcp_tool":false,"description":"Computes gross burn, net burn (expenses minus revenue) and the runway in months from a cash balance, and the projected date the cash runs out when a start date is given.","use_when":"You are a startup or project with a fixed cash pile and want to know how long it lasts at current spending and revenue.","do_not_use_when":"Revenue or costs change month to month (model each month separately) or you need a loan payoff or savings timeline (use debt-payoff or savings-goal).","inputs":[{"name":"cash_balance","label":"Cash balance","type":"number","required":true,"min":0,"max":10000000000000,"description":"Cash and equivalents available today.","example":500000},{"name":"monthly_expenses","label":"Monthly expenses (gross burn)","type":"number","required":true,"min":0,"max":1000000000000,"description":"Total cash spent per month (salaries, rent, tools, marketing).","example":60000},{"name":"monthly_revenue","label":"Monthly revenue","type":"number","required":false,"default":0,"min":0,"max":1000000000000,"description":"Cash received per month; 0 for a pre-revenue company.","example":20000},{"name":"start_date","label":"Start date","type":"date","required":false,"description":"Optional date of the cash balance (YYYY-MM-DD); enables the zero-cash date.","example":"2026-01-01"}],"outputs":[{"name":"gross_burn_per_month","label":"Gross burn","type":"number","decimals":2,"description":"monthly_expenses."},{"name":"net_burn_per_month","label":"Net burn","type":"number","decimals":2,"description":"monthly_expenses − monthly_revenue (negative means cash-flow positive)."},{"name":"runway_months","label":"Runway","type":"number","unit":"months","decimals":2,"description":"cash_balance / net burn (only when net burn > 0)."},{"name":"months_of_expenses_covered","label":"Months of expenses covered","type":"number","unit":"months","decimals":2,"description":"cash_balance / gross burn, i.e. runway if all revenue stopped (only when expenses > 0)."},{"name":"zero_cash_date","label":"Zero-cash date","type":"date","decimals":4,"description":"start_date + runway_months × 365.25/12 days (only when start_date given and net burn > 0)."},{"name":"runway_status","label":"Status","type":"string","decimals":4,"description":"Plain-language summary."}],"input_schema":{"type":"object","properties":{"cash_balance":{"description":"Cash and equivalents available today.","type":"number","minimum":0,"maximum":10000000000000,"examples":[500000]},"monthly_expenses":{"description":"Total cash spent per month (salaries, rent, tools, marketing).","type":"number","minimum":0,"maximum":1000000000000,"examples":[60000]},"monthly_revenue":{"description":"Cash received per month; 0 for a pre-revenue company.","type":"number","minimum":0,"maximum":1000000000000,"default":0,"examples":[20000]},"start_date":{"description":"Optional date of the cash balance (YYYY-MM-DD); enables the zero-cash date.","type":"string","format":"date","examples":["2026-01-01"]}},"additionalProperties":false,"required":["cash_balance","monthly_expenses"]},"output_schema":{"type":"object","properties":{"gross_burn_per_month":{"description":"monthly_expenses.","type":"number"},"net_burn_per_month":{"description":"monthly_expenses − monthly_revenue (negative means cash-flow positive).","type":"number"},"runway_months":{"description":"cash_balance / net burn (only when net burn > 0). Unit: months.","type":"number","x-unit":"months"},"months_of_expenses_covered":{"description":"cash_balance / gross burn, i.e. runway if all revenue stopped (only when expenses > 0). Unit: months.","type":"number","x-unit":"months"},"zero_cash_date":{"description":"start_date + runway_months × 365.25/12 days (only when start_date given and net burn > 0).","type":"string","format":"date"},"runway_status":{"description":"Plain-language summary.","type":"string"}}},"formula":"net_burn = monthly_expenses − monthly_revenue; runway_months = cash_balance / net_burn; zero_cash_date = start_date + runway_months × 30.4375 days","method":"Assumes constant monthly expenses and revenue; the 'default alive' test would instead grow revenue at its current rate. Common guidance is to start fundraising with at least 6–9 months of runway left.","sources":[{"name":"Wikipedia – Burn rate","url":"https://en.wikipedia.org/wiki/Burn_rate","type":"reference","retrieved_at":"2026-09-24"},{"name":"Investopedia – Burn Rate: What It Means and How to Calculate It","url":"https://www.investopedia.com/terms/b/burnrate.asp","type":"reference","retrieved_at":"2026-09-24"},{"name":"Andreessen Horowitz – 16 Startup Metrics","url":"https://a16z.com/16-startup-metrics/","type":"reference","retrieved_at":"2026-09-24"}],"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":"500,000 cash, 60,000 expenses, 20,000 revenue from 2026-01-01","inputs":{"cash_balance":500000,"monthly_expenses":60000,"monthly_revenue":20000,"start_date":"2026-01-01"},"expected":{"gross_burn_per_month":60000,"net_burn_per_month":40000,"runway_months":12.5,"months_of_expenses_covered":8.33,"zero_cash_date":"2027-01-16"},"url":"https://tttkmbb.com/api/v1/calculate/burn-rate-runway?cash_balance=500000&monthly_expenses=60000&monthly_revenue=20000&start_date=2026-01-01"},{"name":"120,000 cash, 25,000 expenses, no revenue","inputs":{"cash_balance":120000,"monthly_expenses":25000},"expected":{"net_burn_per_month":25000,"runway_months":4.8,"months_of_expenses_covered":4.8},"url":"https://tttkmbb.com/api/v1/calculate/burn-rate-runway?cash_balance=120000&monthly_expenses=25000"}],"faq":[{"q":"Gross or net burn?","a":"Gross burn is total spending; net burn subtracts revenue and determines runway. Investors usually quote net burn."},{"q":"What if revenue exceeds expenses?","a":"Net burn is negative, the company is cash-flow positive and runway is unlimited; the calculator reports that status instead of a number."}],"tags":["burn rate calculator","runway calculator","startup runway","net burn","cash runway months"],"related":[{"calculator_id":"mrr-growth","reason":"Project the revenue side over the same months."},{"calculator_id":"add-days","reason":"Date arithmetic for a specific number of days."},{"calculator_id":"break-even","reason":"Sales volume at which burn reaches zero."}],"links":{"html":"https://tttkmbb.com/business/burn-rate-runway","markdown":"https://tttkmbb.com/business/burn-rate-runway.md","json":"https://tttkmbb.com/business/burn-rate-runway.json","api":"https://tttkmbb.com/api/v1/calculate/burn-rate-runway","schema":"https://tttkmbb.com/api/v1/calculators/burn-rate-runway","openapi":"https://tttkmbb.com/openapi.json","mcp":"https://tttkmbb.com/mcp"},"version":"v1","updated_at":"2026-09-24"},"timestamp":"2026-09-24T01:50:59Z"}