Methodology

On most pages, the main rate shown is an indicative mid-market rate.

By "mid-market," we mean a benchmark rate intended to reflect the middle of the wholesale market before a provider adds its own spread or fee. It is useful as a comparison point, but it is not usually the exact retail rate a customer receives.

Unless a page says otherwise, the rates on ExchangeRates.com:

• are benchmarks, not binding quotes
• do not include provider spreads or fees
• may differ from the final rate you receive
• should be used for reference and comparison

On key rate pages, we aim to show five things clearly:

• what type of rate you are looking at
• where the data comes from
• when it was last updated
• whether it is direct or derived
• what is not included, especially provider spreads and fees

We use more than one source so we can prioritise continuity, transparency, and broad coverage.

Primary market data - Our primary source for live and historical exchange-rate data is TwelveData.

Reference data - We also use European Central Bank reference rates as an additional reference source.

Supplementary fiat data - For broader fiat coverage, we also use Open Exchange Rates, which provides hourly rates for 170+ currencies against the US dollar.

Market context - For broader market context, including which currencies and pairs are most actively traded globally, we use Bank for International Settlements survey data.

If we make a material change to our data sources, we will update this page.

We prefer a direct rate when a reliable direct quote is available from our primary source.

If a direct rate is unavailable, we may calculate a derived cross-rate using a major intermediary currency, usually USD or EUR. For example, a less common pair may be calculated through USD or EUR rather than from a direct quote between the two currencies.

If a rate is derived rather than directly quoted, we label it on the page. Direct rates are labelled "Direct rate", computed rates from Open Exchange Rates are labelled "Computed rate", ECB reference rates are labelled "Reference rate", and cross-rates are labelled "Calculated rate" with an explanation of the path used.

Example: a cross-rate calculation. Suppose you look up Thai Baht to Czech Koruna (THB/CZK). There is no widely-traded direct market for this pair, so we look up two legs through US Dollars:

1. THB to USD = 0.02857 (1 Baht buys 0.02857 Dollars)
2. USD to CZK = 23.15 (1 Dollar buys 23.15 Koruna)

Multiply: 0.02857 x 23.15 = 0.6614 CZK per THB. Both legs come from our primary data source. When we do this, the rate display labels it as "Calculated rate" so you know how it was produced.

In practice, converting via two steps could mean paying two spreads. The cross-rate is mathematically correct but your real-world cost may differ.

If neither a direct rate nor a reliable derived rate is available, we may show the most recent available reference rate, delay the update, or temporarily suppress the rate until better data is available.

During market hours, primary rates can refresh as often as every 60 seconds.

Reference rates, such as ECB rates, update less frequently and may appear once per business day.

Where practical, we show the last updated time on page. A timestamp tells you when the data was last refreshed in our system. It does not guarantee that a third-party provider will offer the same rate at that exact moment.

For performance and stability, some pages or widgets may briefly serve cached data. Small timing differences between pages do not necessarily mean the market moved in a meaningful way.

Foreign-exchange markets trade throughout the business week, but they do not update continuously over most weekends.

When markets are closed, ExchangeRates.com may continue to show the last available market close until fresh data is available again. That means a weekend rate is usually a reference point, not a fresh executable quote.

Local bank holidays, thin liquidity, and provider-specific pricing windows can also affect the real-world rate a user receives.

Historical charts on ExchangeRates.com are built from the time series available from our data sources.

Different time ranges may use different levels of granularity. Short ranges may use more frequent observations. Longer ranges may use daily or end-of-period values.

We may backfill or revise historical data if a source corrects an error, updates a series, or improves coverage.

We usually store more precision than we display.

For readability, displayed rates, converted amounts, chart labels, and percentage changes may be rounded. Because of this:

• multiplying a displayed rate by an amount may not exactly match the displayed converted total
• an inverse rate may be calculated from full-precision data and then rounded
• small differences between widgets, tables, and chart labels may reflect rounding rather than a material market move

The basic formula is: Amount x Exchange Rate = Converted Amount

Where relevant, we may also show:

• the inverse rate
• percentage changes over time
• highs and lows
• historical averages
• related cross-rates

These values may be calculated from full-precision data and then rounded for display.

When we publish provider comparison tables, our goal is to help users compare the total outcome, not just the headline fee.

A provider comparison should state:

• the test amount
• the source and destination currencies
• the source and destination country, where relevant
• the funding method
• the payout method
• the timestamp
• whether the figures are live quotes, cached quotes, or estimated benchmark ranges

If a fee is deducted from the amount being converted, we calculate the conversion from the net amount after that fee. If a fee is charged separately, we say so.

If a comparison uses an estimated spread or an industry-typical fee rather than a live quote, we aim to label it clearly as an estimate.

This matters because a low advertised fee can still be a poor deal if the exchange rate itself includes a wide markup.

We run basic checks on the data we publish, including checks for:

• missing or stale updates
• impossible or zero values
• unusually large unexplained jumps versus recent history
• symbol or pair mapping errors
• major conflicts between primary and reference sources

If a rate fails our checks, we may hold it back, flag it, or fall back to a secondary source until the issue is resolved.

ExchangeRates.com covers a wide range of currencies and related assets.

Not every pair is directly traded in deep markets. Some pairs are thin, infrequently updated, or derived through a major intermediary currency.

Some countries also have more than one meaningful exchange rate at the same time, such as official, bank, card, or parallel-market rates. A single public benchmark does not capture every real-world price a user may face.

Unless a page explicitly says otherwise, our default view is the benchmark reference rate, not every possible on-the-ground cash or retail rate.

Unless we explicitly say otherwise, our benchmark rates do not include:

• bank or money-transfer spreads
• card network charges
• cash exchange margins
• ATM or branch fees
• weekend markups
• taxes, duties, or settlement charges
• negotiated rates for large transfers

Our rates are designed for information and comparison.

They may be useful as a benchmark, but they are not a substitute for the source required by your accountant, auditor, regulator, counterparty, or tax authority.

If you need a rate for formal accounting, tax, legal, or contractual use, check the specific rules that apply to you.

If we publish sponsored listings, affiliate links, or commercial comparisons, we aim to disclose that clearly.

Commercial arrangements do not change the benchmark market data shown on our core converter pages.

This methodology page is reviewed whenever we add, remove, or change a data source.

Each review covers:

• Whether data source descriptions match current behaviour
• Whether direct vs derived rate labelling is accurate
• Whether stated update frequencies match system configuration
• Whether any source has been added or removed

Review cadence by page type:

• Methodology page - reviewed at each data source change and at least quarterly
• Pair page templates - reviewed monthly for accuracy of static content, FAQs, and provider fee estimates
• Provider fee estimates - updated quarterly based on published provider pricing pages
• About, FAQ, and Help pages - reviewed at each feature release
• Privacy and Terms - reviewed when data handling or commercial relationships change

Material changes are logged on our updates page.

If you spot a stale timestamp, a broken chart, or a misleading comparison, tell us.

The most helpful report includes:

• the currency pair
• the page URL
• the time you saw it
• a screenshot, if possible
• a short explanation of what looks wrong

We would rather correct a mistake quickly than hide behind vague language.

Corrections log

When we identify or are notified of a data error, incorrect labelling, or misleading content, we fix it and record the correction here.

This log is maintained manually. If you reported an issue and do not see it listed, contact us.