Most "best free AI mastering" lists pad the ranking with services that let you generate a master but lock the download until you pay, then call it free. The honest question is different: which tools actually let you master a track and keep the file at no cost, and where does "free" quietly mean a preview you can hear but cannot export? The answer is narrower than the listicles suggest. For a genuinely free master you can download, the clear pick is BandLab Mastering (free, four preset styles); the most capable free-to-download option is aimastering.com, which gives you an adjustable target loudness with no watermark stated; and Bakuage adds free loudness plus reference matching with real WAV output. The big-name services people expect here, LANDR and eMastered, are not free in the way that matters: they let you preview a master for free but charge to download it. Below we rank by how usable the free option really is, separate genuinely-free-to-download from preview-only, flag every output cap we could confirm, and keep in view one thing free does not change: chasing a loud master is self-defeating because streaming turns it back down. This is general guidance from official sources, not measured audio testing. Figures are as of July 2026; free terms shift often, so confirm the current terms before you rely on them.
Most capable free-to-download: aimastering.com - free with an adjustable target loudness and no watermark stated.
Free loudness + reference matching: Bakuage - free, with reference matching and WAV output.
Free preview only, pay to download: LANDR (unlimited free previews) and eMastered (free A/B preview) let you hear a master free but charge to export.
Free if you distribute there: DistroKid Mixea gives your first track free, tied to a DistroKid account.
The honest caveat: a "free" master is only free if you can keep the file, free tools often cap output to MP3 or a limited format, and free changes nothing about the loudness math: do not chase loud, because streaming normalizes it away.
What "free" actually means for AI mastering
Before the ranking, the definition, because it is where every misleading list goes wrong. In AI mastering "free" comes in three flavors and only one of them is what most people picture. A genuinely free tool lets you master a track and download a usable file at no cost, sometimes with a limited output format. A free preview lets you generate and listen to a master for free but locks the download until you pay or subscribe; this is the model the biggest names use, and it is not free in the sense that gets a track onto Spotify. And a free first track is a one-time unlock, useful but not an ongoing free workflow. Rank a tool by which flavor it is and the field reshuffles fast: the services with the loudest marketing (LANDR, eMastered) are preview-only, while the genuinely free-to-download workhorses (BandLab, aimastering.com, Bakuage) are the ones most lists bury. One more thing free does not change, and it matters more than any of the above: the loudness math. A free master crushed for loudness loses its punch on streaming exactly like a paid one does.
The shortcut: want a real free master you can download today, use BandLab (presets) or aimastering.com (adjustable target loudness). Want reference matching for free, try Bakuage. Treat LANDR and eMastered free tiers as previews you must pay to export, and if you release through DistroKid, your first Mixea master is free. Whatever you use, do not chase loud.
The free-versus-preview reality table
Here is the axis the listicles skip: not just "is there a free tier," but whether that free tier lets you download the file, what format you get, and how much loudness control it gives you. The funding column carries the same honesty standard as the rest of SoundStack, labeling who backs each tool rather than inventing a raise.
| Tool | Genuinely free or preview? | Output cap | Loudness control | Funding |
|---|---|---|---|---|
| BandLab Mastering | Genuinely free (download) | Four presets; free export (format not published, likely MP3 or limited - verify) | Preset styles, no LUFS control | BandLab (whale) |
| AI Mastering (aimastering.com) | Genuinely free (download) | Free, no watermark or cap stated (verify current terms) | Adjustable target loudness + intensity | Japan / independent |
| Bakuage | Genuinely free (download) | WAV 44.1kHz / 24-bit | Loudness maximizer + reference matching | Japan / independent |
| LANDR | Free preview only (pay to download) | Unlimited previews; download is paid ($10/track or subscription), MP3 to HD WAV | Streaming optimization (no explicit LUFS shown) | LANDR (whale) |
| eMastered | Free preview only (A/B vs original) | Subscribe to download (from $9/mo annual); MP3 / WAV | Reference mastering (no LUFS shown) | Challenger |
| DistroKid Mixea | First track free (DistroKid account) | First master free, then tied to distribution | Intensity + EQ, no LUFS shown | DistroKid (whale) |
Free does not change the loudness truth: loud still loses
This is the point that survives whether you pay nothing or a lot, and it is the thing every vendor buries because louder sells. Every major streaming platform normalizes playback to a target integrated loudness so songs play at a consistent level. Spotify's own documentation confirms it targets around -14 LUFS and applies negative gain to anything louder (Spotify loudness normalization). So if a free tool has a "make it loud" button and you push a master to -6 LUFS, Spotify simply turns it down about 8 dB to hit -14, and it plays at the same volume as a well-mastered -14 track, except you crushed your dynamics and transient punch for nothing. The loud version does not win; it loses its life for free. This matters doubly with free tools like Bakuage that are literally built around loudness maximizing: use the reference-matching sensibly, not to chase a number. The honest goal is to make the track sound as good as possible near the platform target and let normalization handle level, with true peak kept below -1 dBTP to avoid distortion. Platform targets below are compiled from Spotify and iZotope's streaming loudness guide; our what LUFS for Spotify guide has the full detail.
| Platform | Normalization target | Notes |
|---|---|---|
| Spotify | -14 LUFS (default) | User can pick Quiet -19 or Loud -11; limiting only at Loud |
| Apple Music | ~-16 LUFS (estimate) | Sound Check; Apple does not publish an official LUFS figure |
| YouTube | -14 LUFS | Always on, never limits |
| Amazon / Tidal | -14 LUFS | Tidal album-normalizes everything |
| Deezer | -15 LUFS | Always on |
| SoundCloud | No normalization | A louder master can make sense here only |
Targets from Spotify's documentation and iZotope's streaming loudness guide. Apple's figure is a community estimate, not an Apple-published spec.
A free tool that boasts a "louder master" is selling you a loss. Master to -6 LUFS and Spotify turns it down to -14 anyway, so you threw away your dynamics for a loudness the platform deletes.Spotify loudness normalization, verified
The free picks, ranked by usable free option
Frequently asked questions
What is the best free AI mastering tool? For a genuinely free master you can download and keep, BandLab Mastering (free, four presets) is the simplest pick, and aimastering.com is the most capable because it gives you an adjustable target loudness with no watermark stated. Bakuage adds free reference matching with WAV output. See the ranking above.
Is LANDR or eMastered actually free? Not for downloading a master. Both let you preview a master for free (LANDR gives unlimited previews, eMastered lets you A/B against your original), but exporting the file is paid: LANDR from $10 a track or a subscription, eMastered subscription-only from $9 a month. They are free to audition, not free to release.
Do free AI mastering tools limit the output format? Often, yes. Free tools tend to cap the download to MP3 or a limited format; Bakuage is a notable exception with real 44.1kHz / 24-bit WAV, and BandLab does not clearly publish its free export format, so verify it if you need a specific delivery file. This is why "free" is worth checking before you build a release around it.
Does a free master sound worse, and does loudness fix it? Quality is subjective and we do not score it, but a good free master on a solid mix is genuinely usable for demos and much of independent streaming; even a working mastering engineer concedes that "AI mastering has matured to the point where many users won't notice the difference from human mastering on consumer playback systems" (engineer review, 2026). What does not help is loudness: streaming normalizes playback to about -14 LUFS, so a free tool's "make it loud" button just gets turned back down and costs you dynamics. See what LUFS for Spotify.
Is there a completely free AI master with no catch? The closest are BandLab, aimastering.com and Bakuage, which let you download a master at no cost. The catches are format limits and the fact that free changes nothing about the loudness rules. If you distribute through DistroKid, your first Mixea master is also free.
Bottom line
Rank free AI mastering by how usable the free option really is, and the honest ranking separates two groups. The genuinely-free-to-download tools let you keep the file: BandLab for a fast preset master, aimastering.com for free with an adjustable target loudness, and Bakuage for free reference matching with real WAV output. The big names people expect, LANDR and eMastered, are preview-only, free to hear and paid to export, and if you release through DistroKid your first Mixea master is free. Remember what free does not change: free tools often cap the output to MP3 or a limited format, so confirm you can keep the file you need, and the loudness math applies no matter the price, so do not chase loud, because streaming normalizes it away and a dynamic master near -14 LUFS beats a crushed one every time. AI mastering, free or paid, is a legitimate and often-sufficient tool, and the honest move is to run the free options on your own track and trust your ears. If you outgrow free and want to set a real LUFS target yourself, a paid plugin like iZotope Ozone gives you that manual control, and services like LANDR and eMastered let you download the preview you liked. This is general guidance, not measured audio testing. For the full picture, see our best AI mastering hub and cheapest AI mastering guide.