LUFS Explained: What Loudness Targets Mean for Your Audio
Your mix is "loud enough" on your speakers — but what will Spotify do to it? LUFS is the number that decides. Here's what it actually measures and how to hit the target without giving your master away.
What LUFS Actually Measures
LUFS (Loudness Units Full Scale) is a measure of perceived loudness, not raw signal level. The EBU R128 / ITU-R BS.1770 standard applies a K-weighting filter — a curve that mimics how human hearing emphasizes midrange and highs while de-emphasizing sub-bass — then averages the weighted energy over time with gating that ignores silence.
The practical consequence: two tracks can have identical peak levels yet very different LUFS — and it's the LUFS number that streaming platforms use to decide how loud you play.
The Target: -14 LUFS (and Friends)
| Platform | Normalization target |
|---|---|
| YouTube | -14 LUFS integrated |
| Spotify | -14 LUFS integrated |
| Apple Music | -16 LUFS (Sound Check) |
| Podcasts | ~-16 LUFS (dialog-based) |
| Netflix | -27 LUFS (dialogue-centric) |
These numbers trace back to EBU R128, the broadcast loudness standard, which streaming platforms adopted for one good reason: normalization means nobody gets blasted or lost when the playlist shuffles. Spotify's move to -14 LUFS in 2017 effectively ended the loudness wars for streaming.
Why Louder Is Not Better
Platforms turn your track down to their target regardless of how loud you master it. Mastering to -8 LUFS therefore achieves exactly nothing except:
- Distortion from pushing the limiter harder.
- Lost dynamics — the quiet parts get crushed.
- Headroom problems — inter-sample peaks can exceed -1 dBTP and get clipped in lossy codecs.
A clean -14 LUFS master with a healthy true peak reads the same perceived volume as a crushed -8 LUFS master — after the platform normalizes both — and the -14 version sounds better doing it.
True Peak: The -1 dBTP Rule
Sample peak looks at the individual samples. True peak reconstructs the actual waveform between samples (4x oversampling) and can find peaks 1-3 dB higher than the sample peak — inter-sample overshoot. Lossy codecs (MP3, AAC) can push those peaks higher still.
That's why streaming platforms reject or clip files above -1 dBTP: it's the safety margin that keeps delivery clean through every codec and playback device. If your true peak reads -0.3 dBTP, the platform's encoder will clip your transients.
Check Without Giving Your Master Away
Your unreleased mix is your intellectual property — uploading it to a web loudness service hands it to a third party before it's public. A local checker avoids that entirely:
- Same standard. The Prescosoft LUFS Loudness Checker implements EBU R128 / BS.1770 with the exact ITU filter coefficients — verified against ffmpeg's ebur128 reference.
- Decoded in-browser. Drop in MP3, WAV, M4A, OGG, or FLAC — the file never leaves your machine.
- Full picture. Integrated LUFS, short-term, true peak, sample peak, loudness range, and platform-target comparison.
Check before you export, adjust once, and ship a master that plays exactly as loud as the label intended — on every platform.
Frequently Asked Questions
What is the difference between LUFS and dB?
dB measures a raw signal level, while LUFS measures perceived loudness after K-weighting — a filter that mimics how human hearing emphasizes mid and high frequencies and de-emphasizes lows. Two files with identical peak dB can sound very different in loudness; LUFS captures the perceived difference. That's why streaming platforms normalize by LUFS, not by peak.
Why is -14 LUFS the standard target?
In 2017 Spotify adopted -14 LUFS integrated for normalization, and YouTube, Apple Music, and most podcast platforms settled on similar targets (-14 to -16 LUFS). These values came from EBU R128, the broadcast loudness standard, adapted for streaming. Normalizing to the same loudness means no track blasts or disappears when the playlist shuffles.
Is louder always better for streaming?
No — it's actively counterproductive. Platforms turn your track DOWN to their target anyway, so mastering to -8 LUFS doesn't make you louder; it just adds distortion and loses headroom. The old 'loudness wars' approach of pushing the limiter hard produces a worse-sounding file that gets normalized to the same perceived level as a cleaner -14 LUFS master.
What is true peak and why does -1 dBTP matter?
True peak measures the actual waveform level after digital-to-analog conversion using 4x oversampling. Inter-sample peaks can exceed the sample peak by 1-3 dB, and codecs like MP3 and AAC can push them higher still. Streaming platforms reject or clip files above -1 dBTP, so mastering with true peak metering avoids surprises at delivery.
How is integrated loudness different from momentary loudness?
Momentary loudness uses a 400 ms window (what you perceive in an instant), short-term uses 3 seconds, and integrated loudness is the whole-file average with gating that ignores silence and very quiet passages. Integrated is the number platforms normalize against — it's the fairest measure of a track's overall loudness.
Can I check loudness without uploading my audio?
Yes — and you should. Uploading an unreleased mix to a web service hands your intellectual property to a third party before it's public. A local tool like the Prescosoft LUFS Loudness Checker decodes and measures the file entirely in your browser using the same EBU R128 standard, so your master never leaves your machine.
Know your loudness before you export
Accurate LUFS and true peak, measured entirely on your device. Nothing uploaded, ever.