Yaak DateAdd Plugin

A Yaak template function plugin that allows you to manipulate dates by adding days, months, or years to the current date and formatting the output.

Features

Add or subtract years, months, days, hours, minutes, and seconds from any date/time
Use current date/time or provide a custom base date/time
Support for negative values to subtract time periods
Flexible date formatting with common format tokens
Smart default formatting (includes time if hours/minutes/seconds are used)
Simple and intuitive interface

Once installed, you can use the dateAdd template function in your Yaak requests:

${[ dateAdd() ]}

Returns the current date in YYYY-MM-DD format.

${[ dateAdd(7) ]}

Returns the date 7 days from now.

${[ dateAdd(0, 3) ]}

Returns the date 3 months from now.

${[ dateAdd(0, 0, 1) ]}

Returns the date 1 year from now.

${[ dateAdd(-7, -1, 0) ]}

Returns the date 7 days and 1 month ago.

${[ dateAdd(0, 0, 0, 'DD/MM/YYYY') ]}

Returns today’s date in DD/MM/YYYY format.

${[ dateAdd(15, 2, 1, 'MMMM D, YYYY') ]}

Returns the date 15 days, 2 months, and 1 year from now, formatted as “January 15, 2026”.

The plugin supports the following format tokens:

Token	Description	Example
`YYYY`	4-digit year	2025
`YY`	2-digit year	25
`MMMM`	Full month name	January
`MMM`	Short month name	Jan
`MM`	2-digit month	01
`M`	Month number	1
`DD`	2-digit day	05
`D`	Day number	5
`dddd`	Full day name	Monday
`ddd`	Short day name	Mon
`dd`	Min day name	Mo
`d`	Day of week (0-6)	1
`HH`	24-hour (2-digit)	13
`H`	24-hour	13
`hh`	12-hour (2-digit)	01
`h`	12-hour	1
`mm`	2-digit minutes	05
`m`	Minutes	5
`ss`	2-digit seconds	09
`s`	Seconds	9
`SSS`	Milliseconds	123
`A`	AM/PM uppercase	PM
`a`	am/pm lowercase	pm
`Z`	Timezone offset	+01:00
`ZZ`	Timezone offset (no colon)	+0100
`X`	Unix timestamp (seconds)	1735000000
`x`	Unix timestamp (milliseconds)	1735000000000

{
  "Authorization": "Bearer token",
  "Expires": "${[ dateAdd(7, 0, 0, 'YYYY-MM-DDTHH:mm:ssZ') ]}"
}

GET /api/reports?start_date=${[ dateAdd(-30) ]}&end_date=${[ dateAdd(0) ]}

{
  "appointment_date": "${[ dateAdd(14, 0, 0, 'YYYY-MM-DD') ]}",
  "follow_up_date": "${[ dateAdd(44, 0, 0, 'YYYY-MM-DD') ]}"
}

MIT

Contributions are welcome! Please feel free to submit a Pull Request.

For issues or questions: