How to use Reaper's Custom Actions

This tutorial shows you how to optimise Reaper for your workflow. It makes use of custom actions where you can program your own macros. An action in Reaper is any input you make, for example, if I click on a MIDI item to select it, that is an action; if I select the next track, that is an action. Custom actions allow you to chain actions together to automate the processes you carry out regularly and save you time. They can also be used for more creative purposes as you will see below.


The first type of action we will look at is a workflow enhancer. These are great because you can assign them to shortcuts or MIDI buttons, and can save you many steps. I'm going to show you how to make a simple custom action where everything is duplicated.

This particular action may not be very useful to some people, but what you have to remember is that everyone's workflow is different, that's why Reaper's ability to customise your own actions is so handy for the users.

The first step to making your first custom item is to figure out what you are doing as you follow through the process manually. Take a note of each selection you make, how you do it, and the order. For this simple one, we want to duplicate everything. So, how would we normally go about this task? I would select everything, hit copy, make sure the cursor was at the end of the selection, then hit paste.

Now we have a plan to work from. Hit "?" or select Actions and then Show Action List, the main photo above shows the menu selection. Once you have the actions list, it will look similar to the image below.

If you are unfamiliar with the actions list, then I recommend you have a look through it. You are able to sort the list by the entry's shortcut key, or its description. You can also search for an action in the Filter bar. This is the window where you can assign your own keyboard or MIDI shortcuts and so will come in handy after you have created your custom actions. We are looking for the Custom Actions at the bottom, hit New next to "Custom Actions" and a new window will pop up. 

The first thing you want to do is name your item. We shall call it "Duplicate Everything", this can be entered in the "Custom Action Name" box (circled in red above). We then can decide on a few options for how this action works. 

I like to select "Consolidate Undo Points" (purple), as that means that hitting undo after carrying out the custom action removes the whole action - leaving it unchecked would mean hitting undo for every step in the action. Finally, before we get onto making the action, you can select whether it shows in the actions menu (green).

To program your custom action, all you need to do is find each step in the actions box, and drag it across in order. Below, I have shown you the first step, I searched "Select all Items" in the filter, found it in the list, then dragged it over. 

And finally, below, you can see the whole custom action. Notice the order in this action, some of the points could move around and others are fixed. For example, you could copy the items either before, or after the cursor was moved to the end. 

If you pasted the items before it was at the end however, they'd paste at whatever position it was at. Notice also, the final stage "Unselect All Items", this isn't strictly necessary, but I have found it good practice to revert back to the original state as closely as possible. It is easy to forget that everything is selected, and every Reaper user has accidentally opened a MIDI item, when 30 others where also selected - it results in all 30 opening at once!

SWS Extensions

You may have heard they exist, but SWS/S&M extensions aren't the obvious solution for many Reaper users. Basically, it is an open source collaboration project, by Standing Water Studios, and a number of other collaborators.

If you download the SWS extensions and incorporate them into Reaper, you will find a vastly expanded list of possible actions to use. This may not be immediately useful if you start out making basic actions, but sooner or later, you will come to a dead end, where there isn't an available action for what you need to do. There is a good chance however that the SWS expansion pack includes it.

One of the biggest additions in the SWS extension is the added possibility for live configurations of Reaper, this is something which I haven't explored much of, but hope to for future articles. There is genuinely too much additional content added by the SWS extension to be able to list it all, so I hope the screenshot below can give some indication to the scale of it - note the scroll bar!

Creative Effects

While the custom actions are mainly beneficial for workflow optimisations, there are a good few creative effects to explore. In a previous article we looked at a crude type of compression/upwards expansion with some interesting results to the sound, completely possible with the custom actions.

One particularly useful action I have made is a shuffler. The way it works is by splitting the item at the grid-lines and using an SWS action to reshuffle the items, before gluing them back together. The custom action is shown below.

Different grid sizes will create different "resolutions" of shuffling, all of which can be used. One option would be to assign a different grid size shuffler to each of the number keys as shortcuts. 

Another thing you can do is include your own custom actions as steps in other custom actions. Below is a picture of a custom action for mapping a MIDI melody across all keys. It is essentially 12 repeats of a previous custom action I made, which transposed a MIDI item up one semitone in a new track.