The reference rate and the card charge can differ
Mei, Tom and Priya’s dinner costs ¥12,000. Their shares, already including the receipt’s tax, are ¥5,000, ¥4,300 and ¥2,700. At an illustrative rate of ¥150 per dollar, the group would estimate an $80 bill. That is an estimate, not a promise about what the card issuer will charge.
Suppose the final card charge is $82.40. Each person reimburses the same fraction of that posted charge as their fraction of the yen bill:
| Person | Receipt share | Calculation before rounding | Owes |
|---|---|---|---|
| Mei | ¥5,000 | 5,000 ÷ 12,000 × $82.40 | $34.33 |
| Tom | ¥4,300 | 4,300 ÷ 12,000 × $82.40 | $29.53 |
| Priya | ¥2,700 | 2,700 ÷ 12,000 × $82.40 | $18.54 |
| Total | ¥12,000 | $82.40 |
The final cent goes to the largest fractional remainder, rather than independently rounding each amount and leaving a mismatch.
What to enter from the receipt and statement
- Identify the items in the original currency. Translate labels if needed, then check quantities, decimals and totals against the paper receipt. Translation does not verify a price.
- Allocate tax and service once. Work out each person’s complete original-currency share before using this tool. Use the itemized calculator if you need to divide shared dishes.
- Wait for the posted charge when reimbursing actual costs. Enter its amount and currency. A pending authorization may change.
- Handle fees explicitly. Add a separately posted fee only if the group agreed to share it and it is not already in the entered charge. A $2.40 separate fee on $82.40 means allocating $84.80, not $82.40.
When a reference rate is enough
A reference conversion can help people estimate a budget or agree on a cash reimbursement. Use one rate and date for the whole bill and keep full precision until the final shares. For example, converting ¥12,000 at exactly ¥150 per dollar gives $80; rounding the inverse rate to $0.0067 before multiplying would give $80.40.
The European Central Bank’s reference-rate page explains that its rates are published for information and discourages using them for transactions. A card issuer or payment service can use a different rate or add fees. Decide together whether you are settling an agreed estimate or the actual cost.
Two payers, cash, and refunds
If two cards paid different parts of a receipt, do not apply one card’s conversion to the entire bill. Allocate each payer’s portion against that payer’s posted amount, then combine the results in the trip calculator. For cash, record the rate or reimbursement amount the group agreed on rather than implying there is a posted card charge.
A later refund may convert at a different rate. Keep the refund’s actual amount and recipient with the original expense, then reconcile the net cost before requesting more money. Do not reuse the original exchange rate and assume it will match.
What this tool does and does not do
It allocates a known converted cost. It does not fetch exchange rates, translate a receipt, access bank data, or transfer money. Supported currency labels are USD, EUR, GBP, CAD, AUD, JPY and KRW; yen and won inputs use whole units. Choosing another label does not convert your input values.