{"uid":"cap_aloXdyAP9WPpqZnWMBHhe","slug":"sindri-coast-fire-calculator-336e115a","name":"Sindri Coast FIRE Calculator","description":"Coast FIRE calculator. Computes the lump sum needed today, invested with zero further contributions, to grow into your full retirement number by your target retirement age, plus (given an ongoing monthly contribution) a year-by-year projection of when your actual trajectory crosses that lump sum.","url":"https://ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws/coastFireCalculator?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"swr":{"type":"number","default":0.04,"description":"Safe withdrawal rate, as a fraction. Default 0.04."},"currentAge":{"type":"number","description":"Your current age in years."},"inflationRate":{"type":"number","default":0.03,"description":"Expected annual inflation rate, as a fraction. Default 0.03."},"retirementAge":{"type":"number","default":67,"description":"Target traditional retirement age. Default 67."},"currentNetWorth":{"type":"number","description":"Current invested net worth."},"monthlyContribution":{"type":"number","default":0,"description":"Ongoing monthly contribution toward currentNetWorth. Default 0."},"investmentReturnRate":{"type":"number","default":0.07,"description":"Expected annual investment return, as a fraction. Default 0.07."},"retirementAnnualSpending":{"type":"number","description":"Expected annual spending in retirement."}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_vq198ku7gyoXVVI0sWTKD","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes the Coast FIRE lump sum needed today to reach your retirement number, plus a year-by-year projection of when your savings trajectory crosses that target given ongoing contributions.","exampleAgentPrompt":"I'm 32 years old with $120,000 invested, contributing $1,500 a month. I want to retire at 67 spending $70,000 a year. What's my Coast FIRE number, and which year will my savings hit it?","exampleUseCases":[{"title":"Early retirement Coast FIRE check","prompt":"I'm 28, have $80,000 saved, and contribute $2,000 a month. I want to retire at 60 with $55,000 a year in spending. When does my portfolio hit Coast FIRE so I can stop contributing?"},{"title":"Mid-career retirement milestone planning","prompt":"Can you calculate my Coast FIRE number? I'm 42, have $350,000 invested, contribute $3,000 monthly, and plan to retire at 65 spending $80,000 a year. Show me the year-by-year projection."},{"title":"Aggressive saver checking coasting feasibility","prompt":"I'm 35 with $250,000 in investments and I put in $4,000 a month. I want to retire at 62 on $90,000 a year. How much do I need as a lump sum today to coast there, and have I hit it yet?"}],"resultDescription":"Returns the Coast FIRE lump sum — the amount needed today invested with no further contributions to grow into the full retirement number by target retirement age — along with a year-by-year projection showing the age and year at which the user's actual savings trajectory (including ongoing contributions) crosses that Coast FIRE threshold, using configurable return rate, inflation rate, and safe withdrawal rate.","failureModes":["Missing required fields (currentAge, currentNetWorth, retirementAnnualSpending) result in validation errors","Retirement age set equal to or less than current age produces invalid timeline","Unrealistically high return rates or SWR may yield misleading projections without error","Negative contribution or net worth values may cause computation anomalies","Lambda cold start may add latency on first call"],"whenToPreferThis":"Choose this endpoint when a user explicitly wants to understand the Coast FIRE concept — i.e. the specific lump sum needed today so that contributions can stop and the portfolio still reaches retirement size through compounding alone. Prefer it over general retirement or FIRE calculators when the crossover trajectory (year-by-year projection of when coasting becomes feasible) is needed, not just a final retirement number.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-19T00:48:22.394Z","isFirstParty":false,"canonicalSlug":"sindri-coast-fire-calculator-336e115a"}