ACF Medium Editor Field



This ACF field type is compatible with:
* ACF 5
* ACF 6

This is an add on plugin for Advanced Custom Fields (ACF) 5 or 6. This plugin will not work if ACF is not installed and active. This plugin may work in a limited capacity if the repeater field is not avilable.

Ever needed to give a client a way to edit the appearence of text without wanting to give them a full blown WYSIWYG editor? Need something less than a WYSYWIG but more than a text or textarea field that you can configure the way you need it to work with the features you need it to have?

This add on for ACF5 adds MediumEditor as an ACF field.
Each field instance is configurable, and each field instance has its own settings. Many of the options
available in MediumEditor are supported, including the creation of custom buttons using MediumButton. It is also possible using either a configuration
setting or a filter to alter the MediumEditor Theme. Some of the available options are covered below.
For more information on MediumEditor and MediumButton, see the description of these libaries at the links provided.

For more information see
Other Notes and

Medium Editor needs your help!. This plugin depends Medium Editor which is the JavaScript package that powers this ACF Add On. I do not maintain this package. This pluig is simply an implementation of it for ACF. Medium Editor is looking for contributors. Without people to help maintain and improve it Medium Editor could fade away and if that happens this plugin will also no longer be possible.

Github Repository

This plugin is also on GitHub

Field Settings

The following is an explanation of the fields, not including the ones that should be self explanatory.

Buttons: These are the buttons that are included in MediumEditor.
Select the buttons you want to include in each editor instance.

Custom Buttons: This is the main reason that I created this plugin. This field supports adding
custom buttons using MediumButton.
Please note that if any of the main fields (Name, Label, HTML Tag) are empty that the entire
button will be ignored.

Name: This is then name of the button and will be used when instaniating the MediumButton Object.
The button name must be unique and cannot be one of the buttons already included in MediumEditor, a
button of the same name as one of the standard button in Medium Editor will not override that button
if it is also included. I do not know what the effects of custom characters in the name will be.
Please report any bugs and I will look into adding something to clean up characters or find some other work-around for any that cause errors.

Label: This is the label that will appear in the button bar. This field allows HTML.
Please make sure it is valid html (I do not validate the html you enter). Invalid markup will probably
break the button bar or the entire admin. MediumButton also supports using icons for buttons.
If you want to use icons in your buttons then it is your responsibility to make sure the icon font set is
available for use in the admin of your site.

HTML Tag: Enter the html tag that will be inserted by this button. Only non-empty html tags are allowed.
Most valid HTML tags are supported. If an invalid HTML tag is entered then the button will be ignored.

I’m not sure at this time what effect some of the tags will have in the editor. I haven’t tried them all
if you run into issues let me know and I’ll need to make a decision on wheter to try to fix it or remove
the tag(s) from the allowed list.

The currently supported tags are: abbr, acronym, address, article, asside, b,
bdi, bdo, blockquote, button, caption, cite, code, del, details, dfn,
div, em, footer, h1, h2, h3, h4, h5, h6, header,
i, ins, main, mark, meta, p, pre, q, s, samp, section, small, span,
strong, sub, sup, summary, time, u, var, wbr

Attributes: Add attributes to the html tag. Attibute names must be valid (they must
begin with a letter and contain only letter, numbers, underscores and dashes. Attribute
values must not contain double quotes (“) any attributes that do not conform to these
rules will be ignored. Please note that beyond this, attribute names and values are not
validated. I do not know what effect invalid entries will have on your admin. Like other
values, if you find something that causes an issue, open one and I’ll see what needs to be done.

Other MediumEditor Options: This is a selection of other
Core Options available for
MediumEditor with the exception of allowBreakInSingleLineInput (see below). Please
see the MediumEditor documentation for information on each of the other options. Selecting
an option will set that option’s value to true, unselecting the value will set it to false.

allowBreakInSingleLineInput: This is an option added specifically for use with WP.
If you set disableReturn on then the medium editor acts like a single line input field. Setting
allowBreakInSingleLineInput allows editors to manually type in <br> tags into these
single line fields to create line breaks.

Medium Editor Theme

MediumEditor fields will use the WordPress theme created specifically for the this plugin unless you change it.
You can alter the theme used for all MediumEditor fields, this is not something that you can apply to only
some fields. You can change the theme on your site in one of two ways:

1) wp-config.php
Add the following code to your wp-cofig.php file

define('MEDIUM_EDITOR_THEME', 'beagle');

2) filter
Add the following code to your functions.php file or wherever you would add such a filter

add_filter('medium-editor-theme', 'my_medium_editor_theme_function');
function my_medium_editor_theme_function($theme) {
  $theme = 'beagle';
  return $theme;

Theme name in the above code is one of the following themes currently supported by MediumEditor:
beagle, bootstrap, default, flat, mani, roman, tim

For more information see MediumEditor and

Custom Editor Styles

The styles used in the medium editor for elementa is inherited from WP. If you want to override these styles
create a file named “medium-editor-syle.css” in your theme folder. If this file exists is will be
automatcially enqueued on all pages where ACF fields appear.

Add Custom Buttons in Code

This filter is applied to the custom buttons before they are validated as having all the correct
requirements that are given when creating a custom button in the field settings for a Medium Editor Field.


  1. acf/medium-editor-field/custom-buttons – filter for every field
  2. acf/medium-editor-field/custom-buttons/name={$field_name} – filter for specific field based on it’s name
  3. acf/medium-editor-field/custom-buttons/key={$field_key} – filter for specific field based on it’s key


  1. $buttons – an array of button options
  2. $field – an array containing all the fields settings for the field being loaded

    // functions.php

    function my_custom_buttons($buttons, $field) {
    $buttons[] = array(
    ‘name’ => ‘red’,
    ‘label’ => ‘Red”‘,
    ‘attributes’ => array(
    ‘name’ => ‘style’,
    ‘value’ => ‘color: #F00;’
    return $buttons;
    add_filter(‘acf/medium-editor-field/custom-buttons’, ‘my_custom_buttons’, 10, 2);

Filter Buttons

This filter is applied to the list of buttons that will be shown. This list will contain the “name”
of each standard button as well as the “name” of each custom button that has been set up for the field.
Please note that only valid button names can be used here. See medium editor’s list of available


  1. acf/medium-editor-field/buttons – filter for every field
  2. acf/medium-editor-field/buttons/name={$field_name} – filter for specific field based on it’s name
  3. acf/medium-editor-field/buttons/key={$field_key} – filter for specific field based on it’s key


  1. $buttons – an array of button options
  2. $field – an array containing all the fields settings for the field being loaded

    // functions.php

    function my_custom_buttons($buttons, $field) {
    // add underline button to all medium editor fields
    // set both the index and the value of the array element
    if (!isset($buttons[‘underline’])) {
    $buttons[‘underline’] = ‘underline’;
    // unset strikethrough if it is set
    if (isset($buttons[‘strikethrough’])) {
    return $buttons;
    add_filter(‘acf/medium-editor-field/buttons’, ‘my_buttons’, 10, 2);


  • Medium Editor field when toolbar is not shown
  • Medium Editor field when toolbar is shown
  • Medium Editor Settings


  1. Copy the acf-medium-editor folder into your wp-content/plugins folder
  2. Activate the Medium Editor Field plugin via the plugins admin page
  3. Create a new field via ACF and select the Medium Editor Field type
  4. Please refer to the description for more info regarding the field type settings


November 17, 2021
Great plugin, thanks a lot! Just perfect if you need limited editor functionality and do not want to use WYSIWYG-Editor. In most of my use cases, the full editor would be an absolute overload.
January 21, 2020 1 reply
Little things that makes editing a site just flawless no more crappy text. Adding custom buttons is the cherry on top of the cake. Just a comment, having the input as a textarea and not just text would be better, or the ability to select between text and textarea, just to give the text more space.
October 7, 2019
I have needed this for a long time. Set the options for the text field to enhance it without having to load the entire editor. Very convenient.
March 26, 2017 1 reply
If it can be integrated into all the ACF field types, will bring ACF to a new level. Recommend!
February 1, 2017
This plugin gives WordPress what it has been missing for some time – a text field that is more than just a textarea and less that tinyMCE. And it does it flawlessly! Recommended.
Read all 6 reviews

Contributors & Developers

“ACF Medium Editor Field” is open source software. The following people have contributed to this plugin.




  • ACF >= V6, prevent initialization of medium editor scripts on ACF Field Group editor
  • Removed custom button settings from field editor, not supported by ACF6. Adding custom buttons is now only available through the filter hook “acf/medium-editor-field/custom-buttons”
  • removed ACF V6 Notice


  • added ACF V6 Notice


  • allow override of plugin input.js src


  • added disc/number list style type in editor to overide WP admin styling


  • improved element targeting and field initialization
  • corrected issue with initialization when using acf blocks


  • increased z-index of toolbar so it won’t be hidden by other modals


  • removed donation nag
  • added enqueing of medium-editor-style.css if it exists in theme
  • updated Medium Editor to 5.23.3


  • Corrected issues with ACF>=5.7.0


  • moved parenthesis to be part of string to be translated and added filter to allow changing the additional field instructions


  • corrected bug


pre> tags being stripped from saved value
* modified the “evaluate html” button icon


  • updated Medium Editor to 5.23.1


  • updated Medium Editor to 5.23.0
  • updated Medium Butoon to latest
  • added new html button for medium editor


  • corrected button style to allow wider buttons for custom buttons
  • abandoned static container, for now, do to incompatibility with Mac


  • corrected bug – in_array() error on line 725
  • css change, fix, work-around for jumpy editor behaviour
  • added delay initialization setting


  • fixed jumpy behavior of editer/toolbar – thanks @Hrohh


  • fixed behaviour of toolbar in safari


  • added WordPress theme to medium editor
  • other changes to make the editor look and feel more like WordPress


  • added missing anchor button missed in 2.1.0 update
  • reverted button order to Medium Editor default
  • corrected bug in custom buttons created in 2.1.0
  • updated screenshots


  • Added dashicons (tmconnect)
  • Added transaltion Support (tmconnect)
  • Added German transaltion (tmconnect)


  • Removed github updater support


  • First released to


  • removed support for nested html tags for custom buttons


  • corrected bug when in clone field


  • correcting bugs


  • initial release