Guide

How to compare two currency deposits

This dual currency deposit calculator guide explains the inputs in ordinary language. Use it to compare two deposit scenarios without treating the result as a product recommendation.

DepositFX is a calculator. It does not open accounts, place deposits, exchange currency or recommend any bank, currency or deposit product.

1. Start with the currency you already hold

The base currency is the money you have today. Enter the amount, annual deposit rate and term in months. This creates the baseline result: how much interest the original currency deposit would estimate at maturity.

2. Add the comparison currency

The comparison currency is the alternative scenario. The calculator converts the base amount using the exchange rate you enter, applies the comparison-currency rate and term, then converts the maturity value back to the base currency for a like-for-like estimate.

3. Read the threshold rate carefully

The threshold rate is the exchange rate where the two estimated maturity values are equal. It is not a forecast. It simply answers this question: at what exchange rate would the comparison-currency result become equal to the base-currency result?

4. Understand exchange spread

Banks and platforms often quote different rates for buying and selling currency. The spread field lets users include a rough conversion cost. If you do not know the spread, leave it blank and treat the result as a cleaner but less complete estimate.

5. Use reference rates as a starting point

If the annual rate field is blank, DepositFX uses the reference rate listed for that currency. Reference rates are meant to reduce manual lookup, not replace the actual product quote from a bank. Product availability, minimum deposit amounts, fees and withdrawal rules may differ.

Before using a number outside the calculator

Worked example: why the exchange rate can change the result

Imagine that you hold CNY 100,000. You compare a 1.5% CNY deposit with a 4% USD deposit for 12 months, using 7.20 CNY per USD and no spread. The CNY path estimates CNY 101,500. The USD path starts with USD 13,888.89, grows to about USD 14,444.44, and converts back to about CNY 104,000 at 7.20. The comparison is therefore about CNY 2,500 higher under these assumptions.

If the maturity rate is 7.00, the USD result is about CNY 101,111 and is lower than the CNY path. If it is 7.40, the result is about CNY 106,889. The calculator shows these scenarios to make the sensitivity visible; it does not forecast which rate will occur.

How the estimate is calculated

DepositFX uses simple interest: interest = principal × annual rate × months ÷ 12. It then adds the interest to the principal, converts the comparison-currency maturity amount back to the base currency, and reports the difference. The model does not automatically compound interest and does not include taxes, fees, deposit-insurance limits, eligibility rules or early-withdrawal penalties.

How reference data is maintained

The source table links to representative public bank pages and shows a checked date beside each rate. Those numbers are reference inputs, not live quotes or promises of availability. Bank products, minimum balances, tax rules and exchange spreads can change. If a link or rate looks outdated, please send the page and the relevant bank source through the contact page.

Read the full calculation method and source policy

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