APR Calculator: Japan

Work out a loan's APR with its fees included, by the method your country's law prescribes: US Regulation Z, the EU and UK APRC, Canada's formula and more.

Reviewed October 17, 2026 by CentExactRates effective June 18, 20101 sourceCalculated in your browser. Shared links include inputs.

The rules for Japan

What the calculator above works from, read from the datasets listed under Data sources. Where a table gives the basis, “set by law” marks a figure fixed by statute or by the body that charges it, and a typical figure is a market convention the calculator opens on, which you can change.

How the jitsunenritsu is calculated
Rule	Value	Basis
Name of the rate	jitsunenritsu	Set by law
Method	Rate per month × 12 (nominal)	Set by law
Stated to	1 decimal place	Set by law
Law	Money Lending Business Act Enforcement Regulation art. 11; Installment Sales Act Enforcement Regulation	Set by law

Japan: a simple yearly rate, to one decimal

The jitsunenritsu, the real annual rate a Japanese lender must show, is defined by the Money Lending Business Act's enforcement regulation as the interest and deemed interest, which includes fees, divided by the sum of each period's available balance multiplied by the length of that period in years. That is a simple rate within the year: for a loan repaid in equal monthly instalments it comes to twelve times the monthly rate, the same method as the American APR, but stated to at least one decimal place rather than two. The Installment Sales Act's regulation applies the same formula to shopping credit.

The rate also matters for a legal limit. The Interest Rate Restriction Act voids interest above 20% a year on a loan under 100,000 yen, 18% up to 1 million and 15% from 1 million, and fees count towards it, so the real annual rate of a cash loan is the figure to check against those tiers.

For how the calculation works, the formula behind it and what it leaves out, see the full guide. For help interpreting a result or comparing it with a quote or statement, read the questions and answers.

Data sources

Dataset	Authority	Effective	Status
Japanese consumer finance conventions	Japan Pension Service	18 June 2010	Within its effective period

Every document each dataset was read from, its notes and how the figures were checked are listed in the guide's data sources.

This calculator in other countries

Where the rules change the answer, a place has its own page that runs the calculator on them and cites the official sources they came from.

CentExactCalculator publisher

CentExact publishes the calculation method, worked examples and available data sources. Automated checks cover reference calculations; they do not certify a result for your circumstances or imply approval by a lender or tax authority.

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This calculator is for general information only and is not financial advice. Results are estimates based on the figures you enter and the stated formula; lenders and providers may round or calculate differently. Check any decision with the institution involved or a qualified adviser.