Methodology & Sources

Timers and duration calculations

The timer and stopwatch tools are browser applications. Countdown durations are converted to milliseconds and checked against an intended end time so normal browser throttling does not make the displayed countdown permanently drift. Stopwatch elapsed time uses the browser clock intended for interval measurement. No online timer should be treated as a safety-critical alarm, and a sleeping device can delay web audio until the browser becomes active again.

Minute conversions on the preset pages are arithmetic: one minute is 60 seconds, so the seconds, halfway points and equal splits shown there are derived directly from the selected duration. Those values do not rely on an external article or estimate.

Time zones and UTC

Civil time is represented with IANA time-zone identifiers such as Europe/London or Asia/Karachi rather than storing a permanent numeric offset. The IANA Time Zone Database records historical and current civil-time rules, including daylight-saving transitions. Reference: IANA Time Zone Database.

UTC is the reference used for offsets and conversions. For background on official time and frequency standards, see the NIST Time and Frequency Division. A local civil time displayed on this site should still be checked against an official local source when the consequence of an error is important.

Sunrise, sunset and coordinates

Sunrise, sunset, twilight and solar-noon results are calculated from a place’s latitude, longitude and date using standard solar-position equations. Small differences between calculators can occur because of rounding, elevation, atmospheric refraction assumptions and the exact definition of sunrise or twilight. For a public reference implementation and explanation, see NOAA’s Solar Calculator.

Coordinates in the bundled city directory are representative city coordinates. They are appropriate for general time and solar calculations but are not a substitute for survey-grade location data.

Prayer times and Islamic dates

Prayer times are calculated from latitude, longitude, date and the calculation-method settings selected for the site. Different recognised methods can use different Fajr and Isha angles, and Asr conventions can differ. Local mosques or religious authorities may also apply local adjustments. For that reason, prayer pages are a calculation aid, not a replacement for the timetable followed by your local community.

Ramadan and other Hijri dates that depend on crescent sighting are labelled as calculated or estimated where appropriate. A local official announcement can differ by a day. When a local authority has announced the date, that announcement should take priority over an arithmetic projection.

Events and optional weather data

Fixed holidays use their calendar rule. Easter-related dates are calculated from the Western Easter rule used by the theme. One-off sporting and public events should use an announced organiser date and are not automatically projected with a guessed recurrence. Event pages are reviewed when a reliable organiser or official calendar announces a change.

When weather is enabled, forecast/current-weather data is requested from Open-Meteo. Weather is inherently changeable; the time shown beside it and the forecast itself should not be treated as an emergency warning service.

How to read the content

Sources are chosen for the claim being made. Primary or official sources are preferred for standards, scheduled events and rules. When a page contains a practical example rather than a factual recommendation, it is written as an example. Health, food-safety, exercise and religious guidance should be checked against the appropriate qualified or local authority rather than inferred from a generic timer duration.