Kaisu-barai, Ribo and the Real Cost of Card Spending
Japanese credit cards give you more ways to pay than almost any card system on earth, and the naming is the first hurdle. 一括払い (ikkatsu) pays in full next month — almost always free. ボーナス一括払い pays in full out of a summer or winter bonus — also usually free. 分割払い (kaisu-barai) splits a purchase into equal instalments. リボ払い (ribo) is revolving: you pay a fixed amount or a minimum each month while the balance rolls on. Only the last two cost money, and this calculator prices both.
With the example inputs — a ¥300,000 purchase at the illustrative 15.00% rate — 12 instalments cost about ¥27,100 each and roughly ¥25,000 in fees. Switch the same balance to revolving with a ¥20,000 fixed payment and it clears in about 17 months for roughly ¥33,000 in fees. At the example minimum (2% of balance, ¥10,000 floor), the same balance takes about 38 months and around ¥80,000 in fees. Same purchase, same card rate, three different outcomes — driven entirely by how fast you repay.
How the instalment maths works
The calculator models instalments the way most issuers describe them: equal payments, interest calculated on the declining balance. Some issuers compute fees as a fixed schedule per instalment count, which lands close to the same total. Your statement is the authority — issuers must disclose the effective annual rate (実質年率) and the fee schedule. Use the statement rate in the box, not a guess.
The revolving trap, precisely
Revolving interest is charged on whatever you still owe. A small fixed payment therefore spends most of itself on interest for years: at the illustrative rate, ¥300,000 at ¥10,000 a month keeps about ¥3,750 of every first-year payment for interest alone. The minimum-payment comparison line in the results card exists because the difference between a minimum and a chosen payment is the difference between a debt that ends and a debt that doesn't. If a payment you enter doesn't even cover the month's interest, the calculator says so in words rather than numbers.
Legal caps and what they mean for your card
Credit card revolving and instalment fees fall under the Installment Sales Act framework, with the Interest Restriction Act caps — 20% under ¥100,000, 18% up to ¥1,000,000, 15% above — as the civil-law boundary. Cards charge a contractual rate; the example 15.00% is a placeholder, and the hint under the box shows which cap applies at your balance. Higher-rate legacy agreements from before the 2006–2010 reforms generated the overpayment refund era (過払い金); if your card rate looks like a number from that era, it is worth a conversation with the issuer.
Frequently Asked Questions
Is リボ払い (revolving) ever a good idea?
Revolving gives flexibility in a bad month, but the maths is unforgiving: interest accrues on the balance for as long as it lives. If you use it, treat the fixed-payment box on this page as your commitment, not the issuer's minimum. The comparison line shows exactly what a minimum costs you.
Why is my instalment amount different from the issuer's?
Issuers disclose their own fee schedules, and some compute fees slightly differently from a declining-balance annuity. This calculator models the standard structure at the rate you enter; your statement is the authority. Totals are typically close.
What rate does my card charge?
Your statement shows the effective annual rate (実質年率) for instalment and revolving balances. The 15.00% pre-filled here is an illustrative example only — NOT a current market rate. The Interest Restriction Act caps (15–20% by balance size) bound what is enforceable.
Is bonus lump-sum payment free?
At most Japanese issuers, yes — ボーナス一括払い settles the purchase from a bonus month payment with no fee, within the issuer's limits. It is one of the genuinely useful conventions of the Japanese card system.
Can this page tell me my payoff date?
It shows months-to-clear for the revolving modes and the instalment count you choose. For a payoff DATE, count forward from your next statement — Japanese cards bill on a fixed day each month, which the calculator deliberately does not guess.
Related Japan Calculators & Guides
- Japan Debt Consolidation Calculator — combine balances into one loan
- Japan Personal Loan Calculator — compare an instalment loan instead
- Guide: Understanding Loan Interest in Japan
- Guide: Debt Consolidation Basics in Japan
Disclaimer: Finance Atlas is not a licensed bank, lender, card issuer or financial adviser in Japan. This calculator provides educational estimates only and does not constitute financial advice or a credit offer. Confirm exact figures with your lender, issuer or bank.