Time Zones From IANA
Every offset, abbreviation and transition is read from the browser own Intl time zone database, so the answers stay current without this page being redeployed.
Date & Time Toolkit
Time zones, meeting planner, date difference and more
Twelve date and time answers, with the daylight saving edge cases spelled out
Web Tool
Official product page
Publisher:
POLPROG
Official product page
12
Panels
7
Direct routes
10
Interface languages
0
Dates uploaded
01 / Date & Time Toolkit
About
Twelve panels: time zones, meeting planner, date difference, add or subtract, business days, recurring dates, age, work hours, Unix timestamp, ISO 8601 and formats, week number and countdown.
The time zone data is the browser's own. Offsets, abbreviations and daylight saving transitions are read through the Intl API from the IANA database the browser ships and updates, rather than from a table frozen into this page. A time zone whose rules changed last year is right here as soon as it is right in the browser.
Daylight saving is handled rather than ignored. When the clocks go back, a local time happens twice; when they go forward, an hour does not exist at all. Most tools silently pick one answer. This one names the case: an ambiguous time is shown with both offsets, and a time that falls in the gap is moved using the offset in force before the jump and says that it was.
A calendar difference is not a subtraction. "One month" is a different number of days depending on which month, so the difference between two dates is measured by walking the calendar rather than dividing a duration, and never reports a negative component. An ambiguous written date - one that could be day/month or month/day - is refused rather than guessed at.
02 / Use case
What it solves
The problem
- Time zone converters quietly pick one answer when the clocks go back and a local time happens twice.
- Date difference tools report things like "0 years, 1 month, minus 1 day".
- Finding a meeting slot across three time zones means three browser tabs and a lot of arithmetic.
The outcome
- Ambiguous and non-existent local times are named as such, with both offsets shown.
- Calendar differences walk the calendar, so no component ever comes out negative.
- A meeting planner that shows every participant's local time on one grid.
Who it is for
- Anyone arranging something across time zones.
- Developers reading Unix timestamps and writing ISO 8601.
- Anyone counting working days, notice periods or an age in exact terms.
03 / Key Features
Key Features
The most important capabilities, explained in practical terms.
Daylight Saving, Named
A local time that occurs twice is shown with both offsets; one that does not occur at all is moved using the offset in force before the jump, and the page says which case applies.
Meeting Planner
Add the participants time zones and see a grid of local times, with the hours that are reasonable for everyone marked and the ones that are not left plainly visible.
Calendar-Correct Differences
Years, months and days measured by walking the calendar rather than dividing a duration - so no component is ever negative, and the round trip back gives the original date.
Business Days and Work Hours
Count or add working days with a chosen weekend, and turn a start time, an end time and a break into a total that agrees with a timesheet.
Seven Direct Routes
Time zone converter, meeting planner, date difference, business days, age, duration and the recurring date generator each have their own page opening straight on that panel, with their own title and description.
Recurring dates
Every second Tuesday, the last working day of the month, every three weeks from a date. A date that does not exist is skipped rather than quietly moved, the count of skips is reported, and the series leaves as CSV or as a calendar file.
Public holidays, filled in rather than assumed
Pick a country and a year and the national holidays are written into the list, where every one of them can be edited or deleted. They are computed from each country's rules - Easter included - not read from a table of dates that quietly goes stale, and regional holidays are never in them.
Straight into a calendar
The hours that suit everybody download as an .ics with the start and end in UTC, so no time zone has to survive the trip. A generated series exports the same way, one entry per date.
04 / Download
Product access
A clear path from the official source to your first successful workflow.
Choose the right platform
Use one of the official links available for your device or browser.
Install or open
Follow the store instructions or open the web application. No third-party installers.
Configure and begin
Review the options, choose your preferences and start with the core workflow.
Official access options
05 / Technology
Technology behind the product
A transparent look at the core technologies used to build and maintain this product.
JavaScript
06 / Security
Privacy & Security
Your data stays on your device. Always.