Add Event date format

Is there an option I'm missing to change the format for the start and end dates when adding or editing an event? Currently it defaults to YYYY-MM-DD, but in the US, we use MM-DD-YYYY. If not, can it be added? If it's a major change, I understand. The only reason I ask is, we have a lot of old people on my site that won't like it.

Edited .

I checked the current JEM code.


The Start Date and End Date fields in the Add/Edit Event form use JEM's `CalendarJem` field, which extends Joomla's own `CalendarField`.

The field definition contains:

`format="%Y-%m-%d"`

but it also uses:

`translateformat="true"`

This means Joomla can replace that format with the calendar date format from the active language (`DATE_FORMAT_CALENDAR_DATE` / `DATE_FORMAT_FILTER_DATE`).

So there does not appear to be a separate JEM option where you can simply select `MM-DD-YYYY` for the Add/Edit Event fields.

It is also worth noting that the date shown on the frontend Event Detail page is handled separately. JEM already has its own configurable frontend date display format, so the format used when entering/editing an event does not necessarily have to be the same as the format visitors see on the event page.

In other words, this question mainly concerns the date input/editing experience rather than JEM's frontend date display.

A configurable or properly locale-aware input format could therefore still be a useful improvement, especially for users who are more familiar with formats such as `MM-DD-YYYY`.

Can I change `format="%Y-%m-%d"` to `format="%m-%d-%Y"` or will that break something else?

You should not change only the format attribute in the JEM XML file.
The field uses translateformat="true", so Joomla replaces that value with the date format defined by the active language. The English (United States) language pack already defines the calendar format as MM-DD-YYYY.

Please install and select English (United States) — en-US as the Administrator language. Also check your individual user profile, because its Backend Language setting can override the site default. If events are edited from the frontend, en-US must also be enabled there.
JEM will display and accept dates such as 08-09-2026, while Joomla safely converts them to the internal database format before saving.

Editing the XML file is not recommended because the change may have no effect while translateformat is enabled, there are separate backend and frontend forms, and the modification would be overwritten by the next JEM update.

If you need more info, check the documentation (updated):
www.joomlaeventmanager.net/documentation/backend/events/add-event

Boy do I feel stupid. I've been running several Joomla sites for over 15 years and every one of them has en-GB installed. I installed en-US and it fixed the issue. Sorry to bother everyone and thank you.