Free Online Mastering
Master your track right in your browser — loud, balanced, and streaming-ready. No signup, no upload, no watermark: every step runs on your device and your audio stays private.
Drop your mix here or click to browse
WAV · MP3 · FLAC · OGG · M4A
Selekt’s free online mastering tool gives your finished mix a loud, balanced, streaming-ready master in seconds — right in your browser. Drop in a WAV, MP3, or FLAC, pick a style, and download a mastered WAV. There is no account, no watermark, and no upload: every step runs on your own device, so your unreleased music stays private.
What is online mastering?
Mastering is the final stage of music production — the polish applied to a finished mix so it sounds loud enough, tonally even, and consistent with commercial releases across phones, earbuds, car speakers, and club systems. Online mastering does that in software instead of a dedicated studio. Traditional online services upload your track to a server and process it in the cloud; this tool runs the same kind of mastering chain — EQ, compression, limiting, and loudness normalization — locally in your browser, so it is free, instant, and private.
How to master a song for free online
- Drop in your finished mix — WAV, MP3, FLAC, OGG, or M4A. It loads from your disk; nothing uploads.
- Pick a style — General/Streaming works for most material, or choose Hip-hop, Pop, EDM, Acoustic, Rock, or Lo-fi.
- Master it — the tool analyzes your track and applies a matching EQ, glue compression, and a true-peak limiter to a streaming loudness target.
- A/B and export — toggle original vs. mastered, check the before/after loudness, and download your mastered WAV.
What loudness should a master be? LUFS targets for Spotify, Apple Music & YouTube
Streaming platforms normalize playback loudness, so chasing the loudest possible master no longer wins — it just gets turned down (and often distorted). The widely used target is about −14 LUFS integrated with a −1 dBTP true-peak ceiling, which is where Spotify, YouTube, and Amazon Music sit; Apple Music normalizes a little quieter, around −16 LUFS. This tool masters to roughly −14 LUFS / −1 dBTP by default and shows you the exact before-and-after loudness, so your track lands in the right range for streaming without clipping.
Free online mastering vs. paid services like LANDR
Paid cloud services — LANDR, eMastered, CloudBounce — upload your track and run reference-matched, ML-tuned mastering on their servers, usually behind a subscription or a per-track fee, often gating the high-quality download. This tool trades that ML tuning for being genuinely free and private:
- Free, no subscription — master as many tracks as you want, no account.
- No upload — your audio never leaves your device, so it is safe for unreleased music.
- No watermark, free WAV — download a full-quality master, not a gated MP3 preview.
- Honest about quality — for a critical commercial release, a human engineer or a paid reference-matched service can still go further. This is a fast, free first pass.
Private by design: master unreleased music without uploading
Producers and composers are rightly cautious about sending unreleased work to a stranger’s server. Because this tool processes everything in your browser with the Web Audio API, there is no upload and no file sitting in a cloud account — the audio stays on your hard drive from start to finish. It is the same local-first principle the rest of Selekt’s tools follow: your work is yours.
When to use a free in-browser master
- Demos and drafts — get a release-level loudness on a rough mix before you share it.
- Beat tapes and loops — bring a folder of beats to a consistent, streaming-ready level.
- Content and video — master a track for YouTube, reels, or a podcast without a queue or a fee.
- A fast first pass — hear your mix “finished” instantly, then decide whether a critical release needs a human engineer.
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Frequently asked questions
Is this online mastering tool really free?
Yes — completely free, with no account, no watermark, and no upload. The mastering runs entirely in your browser on your own device, so there is no per-track cost and nothing to pay for. You can master as many tracks as you like and download each one as a WAV.
Do I have to upload my track or create an account?
No to both. There is no sign up and no upload: your file is read straight from your disk into the browser and processed locally on your device. That makes it a genuinely free online mastering tool with no account and no waiting in a queue — just drop a mix in and master it.
Is it safe to master unreleased music here?
Yes. Because nothing is uploaded, your unreleased music never leaves your computer and never touches our servers — there is no file sitting in a cloud account to leak. If you have ever wondered whether it is safe to upload unreleased tracks to an online mastering site, this tool sidesteps the question entirely: the audio stays on your device.
How does in-browser mastering work?
When you drop in a mix, the tool measures its loudness, true-peak level, and tonal balance, then applies a matching EQ, gentle glue compression, a true-peak limiter, and loudness normalization toward a streaming target (about −14 LUFS, −1 dBTP). All of that is standard mastering DSP and runs on your CPU via the Web Audio API — no AI server, no GPU, no queue.
How loud will my master be (LUFS for Spotify, Apple Music, YouTube)?
The tool targets roughly −14 LUFS integrated loudness with a −1 dBTP true-peak ceiling — the balance Spotify, YouTube, and Amazon Music normalize around (Apple Music sits a little quieter near −16 LUFS). Some styles, like EDM and hip-hop, push a touch louder. You always see the before and after loudness, so you know exactly what changed.
Is there a watermark, and do I get a WAV?
No watermark, and yes — you download a full-quality mastered WAV. Many free mastering tools either stamp a watermark on the preview or only let you export a low-quality MP3 until you pay. This one exports a clean 16-bit WAV for free.
Free online mastering vs. LANDR or BandLab — what is the difference?
LANDR, BandLab, and eMastered are cloud services: you upload your track, their servers process it, and a free tier often gates the high-quality download or adds a subscription. This tool runs the mastering chain in your browser instead, so it is free, needs no account, never uploads your audio, and exports a WAV — at the cost of the reference-matched ML tuning a paid service can offer on a critical release. It is an honest, fast, free first pass.
Will it sound as good as a professional mastering engineer?
It gives you a loud, balanced, streaming-ready master for free, in seconds — perfect for demos, drafts, loops, beat tapes, content, and fast turnarounds. A human mastering engineer or a paid service can still go further on a critical commercial release. This is an honest first pass, not a replacement for a pro on your most important record.
What files can I master, and what headroom should I leave?
Drop in a finished stereo mix as WAV, MP3, FLAC, OGG, or M4A. You get back a mastered 16-bit WAV you can download and release. For the cleanest result, leave a little headroom in your mix (peaks around −6 dB) before mastering rather than a mix already slammed to the ceiling.
Your next step after mastering
Selekt is a workspace for producers and composers — cleared samples, studio tools, and a verifiable receipt for everything you make. Master your track, screen it, then build the next one from a library you can actually clear.
