# Sindri Coast FIRE Calculator

> Sindri Coast FIRE Calculator is a paid API for AI agents from ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-19).

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.

## Facts

- Endpoint: POST https://ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws/coastFireCalculator?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-19
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sindri-coast-fire-calculator-336e115a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_aloXdyAP9WPpqZnWMBHhe

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability sindri-coast-fire-calculator-336e115a -d '<json body>'
```

Example prompt: 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?

## When to prefer this

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.

## Known failure modes

- 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

## How this service works

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.

## Output

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.

## Request schema (JSON Schema)

```json
{
 "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."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/sindri-coast-fire-calculator-336e115a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws](https://www.zero.xyz/host/ppu43fkyhimq5fiqpmo42eh5ri0yypid.lambda-url.us-east-1.on.aws/llms.txt)