Audio Mastering

This tool uses the Web Audio API built into your browser to apply professional mastering processing: parametric EQ, dynamic compression, brick-wall limiting, and LUFS loudness normalization. Your audio never leaves your device — all processing happens locally.

Spotify normalizes to -14 LUFS integrated. If your track is louder, Spotify will turn it down. If it's quieter, Spotify may turn it up (if the user has normalization on). Mastering to -14 LUFS ensures your track plays at the intended volume.

LUFS (Loudness Units Full Scale) measures perceived loudness over time. dBTP (decibels True Peak) measures the absolute peak level of the audio signal. For streaming, you want your LUFS to match the platform target and your true peak to stay below -1.0 dBTP to avoid clipping during encoding.

This tool applies the same core processing chain used in professional mastering (EQ, compression, limiting, loudness normalization). It's excellent for demos, podcasts, social media content, and independent releases. For major releases, a mastering engineer brings trained ears and specialized hardware.

You can upload any format your browser supports — typically WAV, MP3, FLAC, OGG, AAC, and M4A. Output is available as lossless WAV or high-quality 320kbps MP3.

The A/B toggle lets you switch between the original (before) and mastered (after) versions of your audio so you can hear the difference the mastering makes. This is essential for checking that your mastering improves the sound rather than just making it louder.