Transparent calculations

Methodology and Data Source

How the guide combines current hourly EUR/AED, EUR/USD and AED/PHP references, a server-captured EUR/AED intraday trend and transparent daily historical context.

Effective / last reviewed: July 26, 2026

Current and historical data sources

The dashboard requests current EUR, AED and PHP inputs through a secure server-side endpoint connected to Open Exchange Rates. Because the free plan uses USD as its base, the app calculates EUR/AED as AED per USD divided by EUR per USD, EUR/USD as one divided by EUR per USD, and AED/PHP as PHP per USD divided by AED per USD.

Frankfurter remains the source for daily historical EUR/USD, EUR/PHP and EUR/AED observations. Frankfurter dates are preserved exactly as returned and may represent the preceding business day on weekends or holidays.

Source separation: Current EUR/AED, EUR/USD and AED/PHP cards, watches and direct calculations use Open Exchange Rates when available. Historical charts, date comparisons and uploaded-purchase matching use Frankfurter daily observations.

Loading, server cache and browser fallback

  1. The website requests the secure Open Exchange current-rates endpoint when the page opens and approximately once per hour while it remains open.
  2. The server endpoint caches a successful Open Exchange response for about 55 minutes to protect the monthly API allowance.
  3. The website separately requests Frankfurter current and historical daily observations.
  4. The latest successful combined dataset is saved in the visitor's browser.
  5. If one source cannot be reached, the website may continue with the last server-cached or browser-cached value and labels the partial fallback.
  6. If Open Exchange Rates is unavailable and no cached current rates exist, the corresponding daily Frankfurter observations are used as fallbacks.
Date transparency: The current Open Exchange publication time and the Frankfurter historical reference date are separate observations. The “last website check” shows when the browser most recently contacted the services.

Current and historical cross-rate calculations

For the Open Exchange free plan, current EUR/AED is calculated as AED per USD ÷ EUR per USD, current EUR/USD as 1 ÷ EUR per USD, and current AED/PHP as PHP per USD ÷ AED per USD. Historical EUR/AED and EUR/USD are requested from Frankfurter. Historical AED/PHP is calculated from Frankfurter EUR/PHP divided by Frankfurter EUR/AED for the same daily reference date.

Indicative rates: Current, historical and derived rates are informational mid-market or reference values. They are not bank buy rates, sell rates or executable quotations.

How the indicators are calculated

Current comparison

When Open Exchange Rates is available, each current EUR/AED, EUR/USD and AED/PHP rate is compared with the corresponding latest Frankfurter daily observation and historical averages.

Moving average

The arithmetic average of the latest Frankfurter daily observations for the selected window. It smooths day-to-day movement but does not predict direction.

Historical range position

The current or latest reference value's relative position between the lowest and highest observations in the recent historical period.

Volatility

An annualized estimate based on Frankfurter daily percentage changes. Volatility describes the size of past fluctuations, not the direction of the next movement.

Plain-language guide wording

The guide states whether the current reference cost or conversion value is above, below or near its recent Frankfurter historical average. It contains no bid, ask, order-entry or execution controls and does not direct a visitor to buy, sell, delay, hedge or use a particular financial provider.

Personal watches, saved plans and date comparisons

Rate watches and saved calculator plans are stored only in the visitor's browser. EUR/AED, EUR/USD and AED/PHP watches use current Open Exchange rates when available, with Frankfurter daily fallback. Watches are checked only when the page is opened, refreshed or revisited.

The date comparison and uploaded-purchase tools use Frankfurter historical observations because the current Open Exchange endpoint does not provide the historical matching series used by these features.

No prediction: Target levels, historical comparisons and notifications reflect user-defined thresholds and past observations. They are not forecasts or recommendations.

Known limitations

  • Open Exchange Rates and Frankfurter values are not prices available to every customer.
  • The Open Exchange free plan normally updates hourly rather than tick by tick.
  • The intraday EUR/AED dashboard contains only observations captured after deployment; missing hours are shown as incomplete coverage rather than estimated.
  • Actual quotations include spreads, margins, fees, cut-off times and execution conditions.
  • Historical patterns and calculated positioning do not predict future rates.
  • Derived or hybrid cross rates may differ from commercial quotations because of timing, rounding and provider methodology.
  • Data availability depends on the providers, hosting, the secure PHP endpoint and internet connectivity.

Review and corrections

Methodology changes that materially affect outputs will be documented on this page. Suspected data or calculation issues may be reported through the contact page.