Date & Time

The Date & Time settings card controls how PrimeTask displays every date and time across the app - in task details, calendar views, the Day Planner, reports, notifications, and anywhere else a date or time appears. The first time you open PrimeTask, these preferences are auto-detected from your operating system's locale, so most people never need to touch this card. If you want to override the defaults - show European-style dates on a US-configured Mac, switch to 24-hour time, or start your week on Monday - this is where to do it.

Date & Time preferences are local to this device. They don't travel with your Spaces and they don't sync across computers - if you have PrimeTask on both a Mac and a Windows PC, set each machine's preferences independently.

What you can do

Pick the day your week starts on

Sunday or Monday

Pick your date format

US (MM/DD/YYYY), UK/EU (DD/MM/YYYY), or ISO (YYYY-MM-DD)

Pick your time format

12-hour or 24-hour

Turn time bars on or off in Month View

show multi-day tasks as horizontal bars across calendar days, or keep a compact one-item-per-cell view

How to open Date & Time settings

Settings card: Open Settings from the sidebar, then open the Date & Time card.
Settings search: Open Settings and type date, time, format, week start, or calendar.
Command palette: Press ⌘+K (or Ctrl+K), type date or time, and pick the entry.

Things worth knowing

Auto-detected from your system locale

When you first install PrimeTask, the card picks sensible defaults based on your operating system's regional settings. A Mac configured for English (United States) starts with Sunday as the week start, MM/DD/YYYY dates, and 12-hour time. A Mac configured for English (United Kingdom) starts with Monday, DD/MM/YYYY, and 24-hour time. You can override any of those choices independently - the card doesn't lock them together.

Week starts on - Sunday or Monday

Pick whichever week-start convention matches how you think. The card labels them for clarity:

Sunday - US convention. The week starts with Sunday and ends on Saturday.
Monday - ISO 8601 / European convention. The week starts with Monday and ends on Sunday.

The choice affects every calendar view in PrimeTask - the main Calendar, the task calendar, week view, month view, the Day Planner, and anywhere else that lays out a week. The card shows a live preview of the day labels reordering when you switch.

Date format - three choices

Three date formats are available:

US - MM/DD/YYYY - month first, as used in the United States
UK / EU - DD/MM/YYYY - day first, as used in most of the world
ISO - YYYY-MM-DD - year first, the ISO 8601 international standard; also the most unambiguous and the most common format in technical contexts

Each button shows today's date in that format so you can see exactly what you're picking, and a preview below the buttons shows how the format looks in short, full, with-weekday, and numeric variations - so you can confirm the full look before you commit.

The format applies to every date in the app: task due dates, created dates, reminders, reports, calendar headers, timer logs, backup filenames, and anywhere else a date is displayed.

ISO is unambiguous if you work internationally

If you share screenshots or exports with people in different countries, ISO (YYYY-MM-DD) is the only format no one can misread. 03/04 could be March 4 or April 3 depending on the reader; 2026-03-04 can only be one thing.

Time format - 12-hour or 24-hour

Two choices:

12-hour - 3:45 PM
24-hour - 15:45

The card shows the current time in each format on the buttons themselves, so you can see exactly what you're choosing. The format applies everywhere time is shown - task due times, calendar event times, Day Planner columns, notifications, audit logs, and more.

Time bars - Month View only

The Show time bars toggle only affects the Month View in the Calendar. When on, multi-day and all-day tasks appear as horizontal bars that span across the days they cover, so you can see at a glance how long something runs. When off, each day shows a compact list of tasks with no bar rendering.

Time bars look great when you have a handful of long-running tasks on the calendar - projects, trips, all-day meetings. They can feel busy if you have a lot of short tasks stacked on the same days. Try both and keep whichever feels more readable for the way you use the Month View. See Time Bars for the deeper feature guide, and Task Calendar View for the task-specific calendar variant.

Preferences are per-device

Every setting on this card is a local preference - it lives on the device you set it on. Your tasks, projects, due dates, and other data still sync across computers via whatever Space sync you've set up, but the display of those dates and times is controlled per-install. This is the right model for most people: your Work Mac can show 24-hour time while your Home Mac shows 12-hour, and neither machine overrides the other.

If you want the same preferences on a second machine, set them there manually. See Appearance Settings for the other local-only preferences that work the same way (theme, sidebar colours, etc.).

Changes take effect immediately

There's no Save button and no restart required. Pick a new format, week start, or toggle - PrimeTask updates every view and every modal the moment you click. Open a task's details, and the due date is already showing in the new format. The preview panels on the card itself also update live as you change settings, so you can experiment before settling on what you like.

Common questions

"I want my calendars to start on Monday like they do in my country."

Open Settings → Date & Time, and in the Week starts on section click Monday. Every calendar view in PrimeTask - month, week, Day Planner, task calendar, everything - will update immediately to match.

"PrimeTask is showing me American date format but I'm in the UK."

This usually means your operating system is set to a US locale even though you're physically in the UK, so PrimeTask followed the system default. Open Settings → Date & Time → Date format and click UK / EU. From now on, dates will appear as DD/MM/YYYY throughout the app, regardless of what the OS is set to. (If you also want the OS itself to use UK formatting, that's a separate change in System Settings / Control Panel.)

"I hate 12-hour time with AM/PM. How do I switch everything to 24-hour?"

Open Settings → Date & Time → Time format and click 24-hour. Every time display in the app - task due times, Day Planner slots, notifications, calendar events - switches to 24-hour format right away. There's no restart and no leftover 12-hour displays.

"I set this up on one Mac and now my other Mac still shows the old format."

Date & Time preferences don't travel between devices - they're local to each install. Open the card on your other Mac and set it the same way. (Your tasks and their dates still sync normally; it's just the display preference that's per-device.)

"Does changing the date format affect how Quick Add understands dates I type?"

Quick Add parses natural language and common date words like tomorrow, next friday, 25 dec, due:fri, 2027-02-14, and so on - those understanding rules are not affected by the date display format you pick here. See Quick Add Settings and the full Quick Add reference for the exact syntax.

"The time bars on my Month View are cluttering things up. Can I hide them?"

Yes. Open Settings → Date & Time → Time bars display and turn the toggle off. Month View switches to the compact view where each day shows its tasks as a small stacked list instead. You can turn it back on at any time - the toggle doesn't change your tasks, only how they're rendered.

"Will a date I enter show up differently on my teammate's machine?"

Yes, if your teammate has a different date format preference. The underlying date is identical - PrimeTask stores it in a format-independent way - but each person's display reflects their own Date & Time settings. A task due on the 4th of March 2026 shows as 03/04/2026 for a US-formatted teammate, 04/03/2026 for a UK-formatted teammate, and 2026-03-04 for someone on ISO. The dates are the same; only the rendering differs.

Where to go next

If you want to…	Read this
See how calendar views use these preferences	Calendar Overview
Browse every calendar view type	Calendar Views
Use the Day Planner	Day Planner View
Go deeper on time bars	Time Bars
Use the task-specific calendar	Task Calendar View
Set up recurring tasks	Recurring Tasks
Change theme and sidebar appearance	Appearance Settings
Customise Quick Add	Quick Add Settings
Browse all settings cards	Settings Overview