Tags are placeholders in your campaigns and is an essential part of Mailster. They always get replaced with it’s desired content when

  • the campaigns is prepared to send
  • you preview the campaign
  • you visit the webversion of a campaign

You can set them anywhere in your newsletter template with the format {tagname}. Custom field tags are individual for each subscriber.

You can set alternative content with {tagname|alternative content} which will be uses if [tagname] is not defined. All unused tags will get removed in the final message

Check out the “Tags” Tab on the Settings page!

Dynamic Tags

A dynamic tag is wrapped in brackets like the other tags and start with the post type followed by an underscore and the content to display. After a colon can be a negative integer like -3 which represents the third latest entry of the selected post type.

You can also use absolute values like 23 to use the content from the post with the ID 23
Relative tag and Absolute tag explained
Relative Tag
Absolute Tag
Some examples:
  • {post_title:-1} ➨ displays the latest post title
  • {page_title:-4} ➨ displays the fourth latest page title
  • {post_image:-1} ➨ displays the feature image of the latest posts (used in the URL field of the editbar)
  • {post_image:-4|23} ➨ displays the feature image of the fourth latest posts. Uses the image with ID 23 if the post doesn’t have a feature image (used in the URL field of the editbar)
  • {post_content:-1} ➨ displays the latest posts content
  • {post_excerpt:-1} ➨ displays the latest posts excerpt or content if no excerpt is defined
  • {post_date:-1} ➨ displays the latest posts date
  • {post_title:23} ➨ displays the post title of post ID 23
  • {post_link:15} ➨ displays the permalink of post ID 15

Instead of “post_” and “page_” you can use custom post types to.

Available Dynamic Tags

Following tags can be used in your campaigns. All of them use the regular post type post and the last one (-1) as example.
You can replace post with the slug of your post type like page or product:


The relative tag can be replaced with an actual ID of post:

{post_id:-1}Post ID2.0
{post_link:-1}Post Link2.0
{post_permalink:-1}Post Link (same as {post_link})2.0
{post_shortlink:-1}Post Shortlink2.0
{post_author:-1}Post Author, wrapped with a link if {post_author_url} exists.2.2
{post_author_name:-1}Name of the Author2.0
{post_author_nicename:-1}Nicename of the Author2.0
{post_author_email:-1}Email of the Author2.0
{post_author_url:-1}Webaddress of the Author2.0
{post_date:-1}Publish date of the post *2.0
{post_date_gmt:-1}Publish date of the post in GMT *2.0
{post_modified:-1}Last modified date of the post *2.0
{post_modified_gmt:-1}Last modified date of the post in GMT *2.0
{post_time:-1}Publish date and time of the post *2.0
{post_time_gmt:-1}Publish date and time of the post in GMT *2.0
{post_modified_time:-1}Last modified date and time of the post *2.0
{post_modified_time_gmt:-1}Last modified date and time of the post in GMT *2.0
{post_title:-1}The Title of the post2.0
{post_excerpt:-1}The Excerpt of the post2.0
{post_content:-1}The whole content of the post2.0
{post_password:-1}The password in clear letters of the post2.0
{post_meta[meta_key]:-1}The value of a certain [meta_key] of a post2.0
{post_category:-1}The categories of a post, comma separated2.0
{post_twitter:-1}A link to share the post on Twitter2.0
{post_facebook:-1}A link to share the post on Facebook2.0
{post_google:-1}A link to share the post on Google+2.0
{post_linkedin:-1}A link to share the post on LinkedIn2.0
{post_image:-1}The feature image of a post **2.0

* all date and time formats are defined in the General Settings of your site
** The tag you can only use in the URL field of the picviewer

All tags run through a filter mailster_replace_[posttype]_[type]

Append a custom content to the “post_content”
add_filter( 'mailster_replace_post_content', function( $replace, $post, $extra, $campaign_id, $subscriber_id ) {

    // appends custom content
    $replace .= '<br>My custom content';

    return $replace;
}, 10, 5);
Change the date format of “post_date”
add_filter( 'mailster_replace_post_date', function( $replace_to, $post, $extra, $campaign_id, $subscriber_id ) {

    // display as 12th June
    return date( 'jS F', strtotime( $replace_to ) );

 }, 10, 5);

More tags you can use

Next to dynamic tag you can use them in your campaigns.

{unsub}Link to the unsubscribe page *2.0
{unsublink}Address used in {unsub}2.0
{webversion}Link to webversion *2.0
{webversionlink}Address used in {webversion}2.0
{forward}Link to front page which reveals the sharing option *2.0
{forwardlink}Address used in {forward}2.0
{subject}The subject of the campaign2.0
{preheader}The preheader text of the campaign2.0
{profile}Link to the profile page of the campaign *2.0
{profilelink}Address used in {profile}2.0
{headline}Headline used in the notification template file **2.0
{content}Content used in the notification template file **2.0
{link}Link to confirmation **2.0
{linkaddress}Address used in {link} **2.0
{email}The subscribers email wrapped in an anchor link2.0
{emailaddress}The subscribers email2.0
{firstname}The first name of the subscriber2.0
{lastname}The last name of the subscriber2.0
{fullname}The full name of the subscriber2.0
{year}The current year2.0
{month}The current month2.0
{day}The current day2.0
{share:[service]}link to share campaign on [service] ***2.0
{tweet:[username]}latest Tweet of user [username]2.0
{tweet:[id]}Tweet with ID [id]2.0

* the text of the link can get changed on the “Texts” tab in the settings
** only used in a notification template
*** service can either be twitter, facebook, google or linkedin

Add your own dynamic tags

Sometimes you need to add some custom dynamic content to your newsletters. You may use it for coupon codes, custom status or even the weather in a specific region. To achieve that you can start with this snippet

add_action( 'mailster_add_tag', function(){

  mailster_add_tag( 'mytag', 'mytag_function' );


function mytag_function( $option, $fallback, $campaignID = NULL, $subscriberID = NULL ){
     return 'My Tag: Option: '.$option."; Fallback: ".$fallback;

If you add this to your themes function.php you can use {mytag} in your newsletters.
If you add options to the tag like {mytag:my_option} you find this value in the $option variable
To define a fallback value in your tag use {mytag|my_fallback} or {mytag:my_option|my_fallback} to add ‘my_fallback’ in the $fallback variable.