Best 20 Free Synth VST/AU Plugins of 2021!

Last Updated on April 16, 2021.

Here’s a list of the best Free synthesizer VST/AU plugins currently available!

Just download them and have fun!

Here’s a quick table with the 5 Synths that I consider to be the best:

Synth NameFormatOSPrice
DexedVST, AU, LV2 64-bitMac, Windows or LinuxFree
SurgeVST3, AU 64-bitMac, Windows or LinuxFree
HelixVST, AU 32 & 64-bitMac, WindowsFree with optional $75 license
Synth1VST, AU 32 & 64-bitMac, WindowsFree
TyrellN6VST, AU 32 & 64-bitMac, Windows or LinuxFree

Let’s get started…

1. Dexed by Digital Sub Urban (Windows, Mac, Linux)

Dexed is the absolute best Free FM (frequency modulation) Synth currently available, and it is based on the Yamaha DX7.

It isn’t the simplest synth to use… there is definitely a learning curve to it, but I honestly think that it’s well worth investing the time into learning it!

It can even load presets from the DX7 as long as you have a DX7 patch editor and a SysEx manager.

You can access this directory by pressing the “Cart” button and then the “Show Dir” button.

Lastly, the 144 engine parameters of this synth can be automated in the DAW directly from its front panel.

Download it for free here.

Related: Even though all of the plugins on this list are absolutely fantastic, you might also be interested in the best Premium Synth VSTs.

2. Surge by Vember Audio (Windows, Mac, Linux)

Surge is an opensource Synth VST that sounds fantastic and is considered by many to be the best free synthesizer plugin currently available.

It is a hybrid subtractive synthesizer with a dual synthesis engine.

Each patch contain two ‘scenes’, which are separate instances of the entire synthesis engine that can be used for layering or split patches.

In addition to this, it also features three oscillators per voice, 8 oscillator algorithms, Two filter units in 8 different configurations, 12 LFO units available0 (6 are per voice and 6 are global for the whole scene), 7 deformable LFO waveforms plus a drawable/step sequencer waveform, and more.

As far as effects go, it features Delay, Reverb, Chorus, Phaser, EQ, Distortion, Conditioner (EQ, stereo-image control, and limiter), Rotary speaker, Frequency shifter and Vocoder.

Surge used to be a premium plugin and sold for roughly $99, but now it’s free and opensource.

It’s even getting updated consistently, meaning that there will be bug fixes over time and the plugin itself will get better and better.

Download it for free here.

Looking for Premium Synth Plugins? Here’s a post I wrote about the best ones.

3. Tunefish 4 by Brain Control (Windows, Mac, Linux)

There’s a total of four different versions of Tunefish on their website that you could download, but here I will be focusing on the latest one; Tunefish 4..

Tunefish 4 was developed as a smaller replacement for Tunefish 3 with roughly the same power.

It was developed for the intro of “Turles all the way down”. If you want to see the video then here’s a link to YouTube where you can watch it.

One thing that they improved over the previous version is the UI, which will visualize all modulations.

It features 2 ADSRs and 2 LFOs that can be linked to pretty much any important knob using a modulation matrix and effects such as Flanger, Chorus, Distortion, Delay, Reverb, EQ and Formant.

Download it for free here.

Looking for free guitar VST plugins? Here are the 15 best ones.

4. Helix by Audjoo (Windows, Mac)

Helix is a CPU-friendly and highly versatile Synthesizer with a surprisingly high sound quality.

It comes with a lot of presets and built-in effects, as well as three Filters per voice, including traditional low/band/high pass, EQ, and comb, less usual dynamics, three stereo distortion stages, and more.

You need to pay $75 to get the license, but the trial version is virtually fully functional.

If you try it and like it, consider paying the license!

Download it for free here.

Interested in free compression VST plugins? Here’s a post about the 12 best ones.

5. Synth1 by Ichiro Toda (Windows, Mac)

Despite its old age, Synth1 is still extremely relevant today, and this is why I included it in this list, plus it works on both Windows and Mac OS on 32bit and 64bit systems.

This is one of those synth plugins that you should always keep in your arsenal since it sounds absolutely fantastic; it’s right up there with Surge and Dexed, at least as far as freeware synths go.

Synth1 is modeled on the Nord Lead 2 Synthesizer and you can download hundreds of presets for it.

It features two oscillators and one sub-oscillarot, FM modulation, ring mod., synchro, 4 types of filters, distortion, two LFO, arpeggiator, and much more.

It’s extremely light on the CPU and works on almost any OS and DAW.

Give it a try!

Download it for free here.

Interested in free reverb VST plugins? Here’s a post about the 15 best ones.

6. TyrellN6 by u-he (Windows, Mac, Linux)

TyrellN6 is a compact synth that is based on concepts and ideas for a hardware synth: a few modules, novel features, analogue sound and low-cost.

As far as free synths go, it doesn’t get any better than this, and Tyrell N6 is right up there with Dexed and Surge, if you ask me.

The interface has a very “Grungy” look to it and it’s quite intuitive to use, with isn’t that common with synthesizer VSTs.

At its core is a pair of oscillators, a noise generator and ring modulator, plus some ADSR envelopes, and a pair of LFO Modules with eight Waveforms.

Additionally, it comes with over 500 presets to get you started on the right track, and you can even download more of them on the U-He website.

Download it for free here.

7. Exakt Lite (Windows, Mac)

If you’re looking for a user-friendly and intuitive FM Synthesizer, then you need to check out Exakt Lite (ideal for beginners).

This synthesizer isn’t emulating any particular hardware synth, although it does emulate eight waveforms from the Yamaha TX81Z.

It features 4 operators, which can be arranged in the classic 8 FM algorithms and each has different waveforms, like Sine, Saw, etc., and also 12 voices.

The interface is intentionally made for beginners since it makes navigating and using the plugin a breeze.

So, if you’re new to synthesizers, you know which one to get started with.

Download it here for free.

Looking for free Drum VST plugins? Here are the best ones.

8. Tal-Bassline by Tal-Software (Windows, Mac)

Tal-Bassline is a synthesizer especially made for creating super beefy bass lines.

It gives you those acid tones and effects that you hear everywhere.

It’s mostly used in Trap, EDM and other kinds of music where the Bass in emphasized.

If you’re looking for a synth to enhance your song’s low end, Tal-Bassline might be the one for you.

Download it for free here.

Related: Here’s a list of the best free auto-tune plugins which you might find useful!

9. Crystal Synth by Green Oak (Windows, Mac)

Crystal is a semi-modular software synthesizer featuring both subtractive synthesis and frequency modulation (FM) synthesis.

It offers over 90 parameters which may be modulated, multi-stage envelopes with graphical editors, extensive tempo sync of envelopes, LFO rates, and delay times.

It even comes with some built-in effects, such as chorus, flanger, comb filtering, echoes, and a band splitter for effects processing by frequency band.

It also offers wave sequencing, as well as granular synthesis, MIDI Learn, and more.

The interface isn’t the easiest to use, but it definitely sounds amazing.

Download it for free here.

10. Lokomotiv by Archetype Instruments (Windows, Mac)

Lokomotiv is an analog retro synth that sounds absolutely phenomenal as well as being extremely easy to use, which is why I’ recommend it to beginners, just like Exakt Lite.

The UI is very simple and doesn’t look overwhelming at all which is great for anyone who is new to this kind of software.

The way it sounds reminds me of some Prince songs…

If you’re looking for an easy to use- and retro sounding synth, this is the one!

Download it for free here.

11. Digits by Extent of the Jam (Windows, Mac, Linux)

Digits is a phase distortion synthesizer plugin that was inspired by the Casio CZ line.

It comes with over 100 presets, including; basses, leads, pads, pseudo-realistic instruments, brass sounds and more.

It provides some effects like an analog chorus, flanger, harmonic bit crush, asymmetric pitch-bend and more.

This is another one of those synthesizers designed with ease of use in mind. Granted, it’s not as simple to use as Exakt Lite, but beginners shouldn’t have any issues with it.

The only problem I encountered is that when you change some parameters the audio can sometimes click a bit, but other than that it’s an amazing plugin.

Download it for free here.

12. Tal-NoiseMaker by Tal-Software (Windows, Mac)

Tal-NoiseMaker is based on the Tal-Elek7ro but with a new synth engine and some sound and usability improvements.

It’s got dual oscillators, a multi-mode filter, two LFO modules, and a set of built-in effects, such as reverb, chorus and a simple bit crusher.

In addition to this, it comes with 128 built-in presets that you can use.

This free instrument is definitely one that you should try and have in your collection, since it sounds great right from the get-go and the interface is really clean and easy to use.

Download it for free here.

13. MauSynth (Windows, Mac)

MauSynth is a polyphonic analog-modeling subtractive synthesizer that allows you to create some pretty interesting sounds with it.

It is especially useful for EDM, and you may have Noticed that the name of the plugin sounds a lot like the artist DeadMau5, and it does recreate his sound quite well.

In fact, many of the presets are directly named like the artist…

Speaking of presets, it does come with a few and they all sound absolutely fantastic!

If you’re into EDM, then I can’t recommend MauSynth enough!

Download it for free here.

14. PG-8X by Martin Lüder (Windows, Mac)

The PG-8X is inspired by the Roland JX-8P, and it does sound almost identical to its hardware counterpart, with the clear advantage of being completely free!

The plugin is available for Windows and Mac OS, in both 32- and 64-bit formats.

Now, you can use it to create analog-style sounds, including string ensembles, really nice bass sounds, and more.

It’s considered by many to be the absolute best free synthesizer out there, especially for reproducing that 80s’ analog sound that we all know and love.

This is a “must-have” in my opinion, since it’s rare to find such high-quality software for free.

Make sure to check out the developer’s website and download it there.

Download it for free here.

15. Charlatan by BlauKraut (Windows)

Another top contender on this list is Charlatan, especially if you value ease of use;

Charlatan is a polyphonic, subtractive virtual analog synthesizer plugin that focuses on sound quality and ease of use by providing a streamlined and intuitive interface.

Its engine features two oscillators, two ADSR envelopes, an LFO module, a multi-mode filter, and unison with up to 7 voices and stereo spread.

Lastly, not only is Charlatan easy to use, but it also goes extremely soft on your CPU, using very little resources.

Just like the previous one on this list, the PG-8X, Charlatan is one of my top recommendations, even though it’s only for Windows.

Download it for free here.

16. Helm by Matt Tytel (Windows, Mac, Linux)

Helm is a cross-platform, polyphonic subtractive synthesizer that runs as a standalone synthesizer, or as an LV2, VST, VST3 or AU plugin, in either 32- or 64-bit.

While it’s definitely not as easy to use as other synths on this list, like Charlatan, it does manage to fit all the controls and features on-to its main windows, meaning that you don’t need to search through endless menus to get to where you want.

It is one of the few free synths out there that can be used to create glitchy sounds, and this is because it features a “stutter” effect, usually only available on paid plugins.

Lastly, Helm is open source, which means that you can modify it and even redistribute your own modified versions.

Download it for free here.

Looking for free Modulation VSTs? Here’s a post I wrote about the best ones.

17. Podolski by u-he (Windows, Mac, Linux)

Podolski used to be my go-to synth a couple years ago, and it is a very simple, CPU-efficient virtual analogue synthesizer that features one oscillator, one filter, one envelope and two LFOs.

Additionally, it also features a Zebra-style arpeggiator/sequencer plus chorus and delay effects.

Not only this, but U-He is consistently updating it and adding new features, presets (over 300 now), etc.

This one absolutely gets my vote!

Download it for free here.

18. OB-Xd by discoDSP (Windows, Mac, Linux, iOS)

OB-Xd 2.2.

The OB-Xd is a subtractive synth that emulates the Oberheim OB-X, OB-Xa, and OB-8 analog synthesizers.

It doesn’t try to 100% recreate the sound, but rather improve on some key aspects, which is why they added some additional features when compared to the original hardware synths.

This plugin comes with an impressive number of presets that try to recreate the sound of the OB-X, as well as de-tunable oscillators with unison, a noise generator, a pair of envelopes, a great-sounding filter, and an LFO.

Lastly, not only does the OB-Xd work on windows and Mac, but also on Linux and iOS devices.

Download it for free here.

19. T-Force Alpha Plus by Master Code Music (Windows)

T-Force Alpha Plus is the improved version of the T-Force Alpha TS.

It provides all the same features, plus some more, and updated functions; new synthesis (subtractive and FM synth), revised oscillators, new Mod Envelopes, and a new integrated sidechain FX.

This synth is especially useful for trance- and electronic music.

Download it for free here.

20. Zebralette by u-he (Windows, Mac, Linux)

Zebralette offers just one of Zebra2’s oscillators packed into a simple- easy-to-learn framework.

If U-He decided to make an entire plugin out of just one oscillator from Zebra2, imagine how powerful Zebra2 actually is!

You can customize the Oscillator waveform with geomorph, spectromorph, geoblend and spectroblend modes, as well as add 24 spectral effects including filter, sync, scatter, phase distortion and many more.

Zebralette is a great starting point and it will also teach you the basics of how Zebra2 works, should you ever want to upgrade.

Download it for free here.

Honorable Mention

This one didn’t make the list because it’s not strictly a synth, but it sounds awesome and it’s completely free which is why I included it.

LABS by Spitfire Audio

Spitfire Audio released a series of instrument plugins which they called LABS.

These aren’t synths but rather sampled instruments, but they sound awesome…

Spitfire Audio is known for making extremely good sounding sample libraries and these ones are no exception to this rule.

Here you will have a huge variety to choose from, from scary strings, to modular piano, cool sounding choirs, synth pads, drums and more.

They offer a huge number of options so here’s the link to the official website where you can check all of them out.

Spitfire Audio LABS official Website.

My top recommendations

It’s definitely hard to choose only three plugins out of the eighteen on this list, but my top choices would have to be;

And last but not least…

How can you learn to use a Synth the right way?

If you really want to learn as much as possible about synthesizers without wasting too much time, then I’d recommend enrolling in an online course like Beginner’s Guide to Synthesis.

This course covers all the basics and all the essential knowledge you need about synthesizers in order to produce modern music.

You’ll need a MIDI Controller

In order to be able to use these plugins properly, you will need some sort of MIDI Controller.

While you can use your mouse to map the MIDI in your DAW, it’s a lot faster and easier to do it with a keyboard/controller.

My recommendation here is for you to get something like the M-Audio Oxygen 25 MK IV MIDI Controller which you can find at Amazon at a very affordable price, plus it comes with some extra software like Pro Tools First.


Since all of these synth plugins are completely free, I’d recommend that you try as many as possible, especially since each one might be a bit better at doing something in particular.

I hope this list was useful to you!

Have a great day!

Frequently Asked Questions

What is a VST synth?

VST Stands for Virtual Studio Technology and it is an audio plug-in software interface that integrates software synthesizer and effects in digital audio workstations. VST and similar technologies use digital signal processing to simulate traditional recording studio hardware in software

What is a VST effect?

VST stands for Virtual Studio Technology and there are three different types of VSTs;VST instruments: These plug-ins generate audio and are either virtual synthesizers or samplers that emulate how the original hardware sounds.
VST effects: Effects process audio instead of generating it. These effects are; Reverb, Relay, etc.
VST MIDI effects: MIDI plug-ins process MIDI messages and send MIDI data to other VST instruments and hardware.

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