# Loopin Mastering — free online audio mastering

> Master your song online, free. Upload an MP3 or WAV, pick a feel, compare Original vs Mastered, and download a streaming-ready WAV — processed entirely in your browser. No account, nothing uploaded.

## What it is

Loopin Mastering is a free, in-browser audio mastering tool. Everything runs locally on your device — your audio never leaves the browser and nothing is uploaded to a server.

## How to use it

1. Upload an MP3 or WAV (or most formats the browser can decode).
2. Pick a feel (preset).
3. Compare Original vs Mastered, and check the before/after meters.
4. Download the mastered WAV.

## Feels (presets)

- **Warm** — round low-mids, soft top, analog glow. Jazz, indie, lo-fi.
- **Punchy** — tight, hard-hitting lows and sharp attack. Hip-hop, trap, pop.
- **Crisp** — bright, airy and detailed. Pop, R&B, acoustic.
- **Wide** — big stereo image with the bass kept mono. Electronic, pop.
- **Vintage** — tape colour and a gentle high-end roll-off. Soul, rock, lo-fi.
- **Club** — loud, smiley, club-ready energy. EDM, hip-hop.
- **Lo-fi** — narrow, hazy and intimate. Lo-fi, chill.
- **Cinematic** — deep, wide and dynamics-preserving. Score, ambient.

## The chain

Corrective EQ, a custom multiband compressor, character EQ, saturation, M/S stereo width (bass kept mono), two-pass ITU-R BS.1770 loudness targeting (about −14 LUFS for streaming, hotter for club) and a true-peak limiter at a −1 dBTP ceiling. Output is exported as 16-bit WAV with dither.

## Good to know

- Free, no sign-up or account.
- Nothing is uploaded — processing is 100% on your device.
- Part of Loopin, the songwriting app for iOS: https://onloopin.com/

## Mastering guides

- How to master a song online: https://onloopin.com/mastering/how-to-master-a-song-online
- Mixing vs mastering: https://onloopin.com/mastering/mixing-vs-mastering
- What is LUFS?: https://onloopin.com/mastering/what-is-lufs
- Master for Spotify, Apple Music & YouTube: https://onloopin.com/mastering/master-for-spotify-apple-youtube

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Source: https://onloopin.com/mastering