Retirement calculations.
Explicit assumptions.

Use a calculator · OpenAPI contract · Country and input catalog

Which calculations are available?

API v1 covers UK pension drawdown, Australian super accumulation and retirement spending, and pension-income gaps for 35 other countries. Those 35 models use your own pension forecasts after tax; they do not calculate national entitlements. Contribution-cost and current-year policy tools are outside this API.

Make one calculation

1. Read GET /api/v1/catalog to choose a country and its input schema. The UK code is uk.
2. Send POST /api/v1/calculate with Content-Type: application/json and all required assumptions.
3. Keep the returned units, assumptions, warnings and source links beside any displayed result.

No API key is required. Send one scenario per request, up to 16 KiB. Do not put inputs in the URL. Numeric strings, extra fields, invalid ages and missing assumptions are rejected. includeProjection: true adds annual cash-flow rows; the default is a compact summary. UK and Australian calculations stop if the published rule-review deadline is reached.

{
  "country": "uk",
  "input": {
    "age": 65,
    "endAge": 95,
    "pot": 300000,
    "monthlyWithdrawal": 1000,
    "growth": 0,
    "fees": 0,
    "inflation": 0,
    "increaseWithdrawals": false,
    "takeTaxFreeCash": false,
    "remainingAllowance": 268275,
    "region": "rest",
    "otherIncome": 0,
    "statePension": 0,
    "statePensionAge": 67
  }
}

Three checks you can reproduce

These invented, zero-return examples verify arithmetic. They do not represent a typical pension or a recommended plan. Each button sends only the displayed example to this site's API, never values from another calculator.

• UK: £300,000 ÷ £1,000 per month = 300 withdrawals. With zero return, fees and inflation, starting at 65, the pot reaches zero at age 90. This checks gross withdrawals, before the separate income-tax illustration.
• Australia: A$300,000 ÷ 25 years = A$12,000 per year, or A$1,000 per month, with zero return, fees, inflation and Age Pension. This is a capital-spending budget before personal income tax.
• Japan income gap: ¥200,000 spending − ¥100,000 entered monthly pension = ¥100,000 monthly gap. Over 30 years at zero real return, required capital is ¥36,000,000.

Choose an example above.

How do I interpret the response?

summary contains the calculated amounts; units defines each field's period and money basis. A null depletion or shortfall age means none occurred within the chosen horizon, not that the plan lasts forever. An alternative level budget is different from the result of your entered spending target. Calculations keep full precision; round only when displaying amounts.

The API reuses the published model version 1.0. Its interface version is separate from the rule-source review date. The response echoes the supplied assumptions so you can reproduce the scenario. Official links are reference sources, not endorsements.

Errors and safe use

400 means invalid JSON or a query string; 404 an unknown API path; 405 an unsupported method; 413 an oversized body; 415 a non-JSON body; 422 invalid input; 503 a rule review is due. Correct the problem before trying again. Do not turn an error into a zero-valued financial result. Hosting limits or service errors may return other status codes; always check HTTP status.

What happens to the data?

Ordinary calculator pages process inputs in the browser. API callers deliberately send parameters to our Cloudflare-hosted calculation service. The application does not log or store request bodies or results, call an AI provider, or send financial data to analytics. API responses are marked no-store. Hosting providers and the caller's own AI application can process data under their own policies. Do not send names, contact details, account numbers or identifiers. Read the data-processing details.

Can Google AI Mode call it?

This is an independently callable HTTP API with an OpenAPI contract. Google Search AI Mode has not been connected or verified. Providing a contract does not register a tool with Google. Developers can use an HTTP-capable client and verify its actual requests and results. Google's AI search guidance covers search eligibility separately.

All results are educational illustrations, not personal financial advice, eligibility decisions or transaction recommendations. Use your own confirmed pension estimates and check the scope of use. For a reproducible error, send an invented example and the model version.