What Is a VST Plugin? VST, VST3, AU, AAX and CLAP Explained

A VST plugin is a piece of software, either an instrument or an effect, that loads inside your DAW to generate or process audio. VST stands for Virtual Studio Technology, the plugin standard created by Steinberg, and it's the most widely supported plugin format on Windows and Mac.

Think of your DAW as the studio and plugins as the gear. A reverb plugin replaces a hardware reverb unit, a synth plugin replaces a keyboard, and you can load as many copies as your computer can handle. VST is one of several formats those plugins come in, and which one you need depends on your DAW.

What does VST stand for?

VST stands for Virtual Studio Technology. Steinberg introduced it in the mid-1990s with its Cubase VST software, so that outside developers could build effects that ran inside the program. A later version added MIDI input, which made software instruments possible. Those are often called VSTi, with the i for instrument.

VST3 is the current version. Steinberg no longer offers the older VST2 development kit to new developers, which is why most new plugins ship as VST3 and some skip VST2 entirely.

Types of VST plugins

• Instruments (VSTi): synths, samplers, drum machines and virtual pianos. They take MIDI notes and produce audio.
• Effects: EQs, compressors, reverbs, delays, saturation and so on. They take audio in and send processed audio out.
• MIDI effects: arpeggiators, chord generators and similar tools that transform MIDI before it reaches an instrument. Support for these varies by DAW.

All five of our plugins are effects. Two of them, Pump (a tempo-synced volume shaper) and Spread (a stereo widener), are free, which makes them an easy way to check your plugin setup works.

VST vs VST3: what changed?

VST3 is a rewrite rather than a small update. For you as a user, the practical differences are:

• Proper sidechain inputs, so compressors and gates can be keyed from another track in a standard way.
• Smarter processing, where a plugin can stop using CPU when no audio is passing through it.
• One file format on both platforms. VST3 plugins use the .vst3 extension on Windows and Mac. VST2 used .dll files on Windows and .vst bundles on Mac.
• A standard install folder, so DAWs find VST3 plugins automatically. VST2 never had one on Windows, which is why old plugins ended up scattered across the drive.

VST vs VST3 vs AU vs AAX vs CLAP

VST isn't the only format. Apple, Avid and a pair of independent developers have their own, and the format a plugin uses has to match what your DAW supports. The audio processing is normally identical across formats; only the wrapper changes.

CLAP (CLever Audio Plug-in) is the newest of the five. It's an open-source format developed by Bitwig and the synth maker u-he, aimed at better multi-core performance and modern features. Support is spreading, so check your DAW's documentation if you want to use it.

For a deeper comparison of Audio Units and AAX, including the exact install folders for each format on Mac and Windows, read our guide to VST vs AU vs AAX.

Which DAW uses which plugin format?

Format support changes between versions, so if a plugin doesn't appear, check your DAW's current documentation. Our own plugins come as VST3, AU and AAX, which covers every DAW in the table.

Which format should you install?

• Windows, any DAW except Pro Tools: VST3.
• Mac with Logic Pro or GarageBand: AU.
• Mac with Ableton Live, FL Studio or Studio One: VST3 or AU. Either works; pick one so your plugin list doesn't show duplicates.
• Pro Tools on either platform: AAX.

Installing every format is harmless. You'll just see the same plugin twice in some DAWs, and most let you hide one format in their settings. See our guide to installing plugins in Ableton Live for that exact setting, or our pages for Ableton, FL Studio and Pro Tools.

How do you use a VST plugin?

1. Install it. Run the developer's installer and choose the formats you need. It copies the plugin into the standard folder for each format.
2. Let your DAW find it. Most DAWs scan for new plugins on launch. Some need you to enable a folder or press a rescan button in their settings.
3. Load it. Effects go in an insert slot on a track, or on a return track if several tracks will share them (typical for reverb and delay). VST instruments go on a MIDI or instrument track, where they play the notes you program.
4. Save presets. Once you've dialed in a sound you like, save it as a preset so you can recall it in the next session.

64-bit and Apple silicon

Current DAWs are 64-bit only, so old 32-bit plugins won't load without a third-party bridge, and many won't work even then. On Macs with Apple silicon, a plugin needs a native (Universal) build to load in a DAW running natively. Older Intel-only plugins usually need the DAW itself to run under Rosetta.

If a plugin installs fine but never shows up, a mismatch here is one of the first things to check, along with the format and the install folder.

Are VST plugins safe?

Plugins from the developer's own website or an established store are as safe as any other software. Cracked plugins are a different story: they're a well-known route for malware onto music computers, and they're illegal. With so many good free VST plugins around, there's no reason to take the risk.