YouTube Audio Loudness Checker & Fixer
Normalize YouTube audio to -14 LUFS
Measure the soundtrack, compare a short before-and-after preview, then fix only the audio. The video stream is copied where MP4 allows it. −14 LUFS / −1 dBTP is the WoluTools default, not a YouTube rule; you can set your own target.
START HEREChoose mediaMP4, MOV · MP3, WAV, M4A, FLAC, OGG
Free: 3 jobs/day up to 10 MBPro: up to 4 GB, 200 jobs/day All limits
- No account needed for free jobs
- Failed jobs are never counted
- Result kept 24 hours
EXAMPLE RESULTSample data
Soundtrack measured · 18:42
Integrated−19.6 LUFS
True peak−0.2 dBTP
✓ Preview ready · video stream preserved
Fixed MP4 · report · timeline
- Integrated
- −19.6 LUFS
- True peak
- −0.2 dBTP
- Range
- 17.4 LU
Formats, limits & file handling
- Works with
- MP4, MOV · MP3, WAV, M4A, FLAC, OGG
- Free
- 3 jobs a day · 1 file up to 10 MB and 15 minutes · no account needed · failed jobs are never counted · resets at midnight UTC
- Pro
- Up to 200 jobs a day · €12.99/month or €89.99/year · See plans
- Largest file
- 1 file · video 4 GB / 120 min · audio 500 MB / 180 min · files above the free limit need Pro
- You receive
- Fixed MP4, M4A or WAV plus HTML report, timeline CSV and manifest
- File handling
- Measurement draft 2 hours · result 24 hours
Upload one finished video or audio file, see exact loudness evidence, compare a short original and recommended preview, then choose whether anything should change.
THREE CLEAR STEPS
From your file to normalized audio.
- 01Choose one file
MP4 or MOV video, or MP3, WAV, M4A, FLAC or OGG audio.
- 02Read the measurement
Integrated LUFS, true peak, loudness range and a timeline. Compare a short original and recommended preview.
- 03Pick a mode and download
Measure only, preserve dynamics, even out spoken voice or a custom target. Failed jobs are never counted.
Interactive synthetic measurement
Hear the decision, not just a number.
This fictional 18-minute soundtrack stays in the browser. The controls change prepared evidence only; no media is uploaded.
✓
No public uploadPrepared soundtrack
WoluTools default −14Long silence
Peaks may clip or distort−0.2 dBTP · listen near 07:14
Spoken level changes are wide17.4 LU range
Long silence needs review6.8 seconds near 12:03 · never removed automatically
Prepared original · 12 seconds
Prepared packageyoutube-audio-fixed.mp4audio-analysis.htmlloudness-timeline.csv · processing-manifest.json
Prepared source measurement shown.
Audio evidence before a volume change
Measure the complete primary soundtrack
A single waveform or peak meter cannot explain why a video feels quiet, exhausting or inconsistent. WoluTools decodes the complete primary audio stream locally and uses EBU R128 measurement for integrated loudness, true peak and loudness range. A second-by-second timeline exposes large level swings, while deterministic checks mark long silence, likely clipping and notable left/right RMS imbalance.
The result never claims that one number is an official YouTube requirement. The visible WoluTools default is a practical processing starting point. Music, dialogue, ambience and intentionally dynamic work can need different creative choices, so the report keeps automatic evidence separate from a manual listening checklist.
Listen before confirming a fix
After measurement, the private app creates a short original M4A preview and a recommended processed preview from the same section. The user can compare them before selecting Measure only, Normalise while preserving dynamics, Even out spoken voice or a bounded custom target. Silence is reported but never removed. Noise, distortion and a poor mix are not presented as automatically repairable.
Preserve dynamics uses two-pass loudness normalisation with a true-peak ceiling. Speech mode adds restrained, fixed compression before its own two-pass measurement. A confirmed hash binds the measured source, engine version and selected target, preventing an unnoticed change from entering the package.
Keep video quality and output evidence
For MP4 and MOV sources, the primary video stream is copied into the output whenever the supported MP4 path permits it; only the primary audio becomes AAC at 48 kHz. Audio-only sources can produce M4A, 24-bit WAV or both. Every media output is probed and measured again before packaging. The manifest records input and output hashes, actual verified loudness, target, mode and pinned engine version.
YouTube creatorsUnderstand why one upload sounds much quieter or more aggressive than the rest of the channel.
PodcastersReduce wide dialogue swings before turning an episode into a video.
EditorsDeliver a fixed media file with exact measurement evidence instead of an unexplained gain change.
Teachers and teamsCatch accidental silence and channel imbalance before a long publishing workflow.
Before processing audio
YouTube audio loudness FAQ
Exact answers about targets, video quality, previews, formats and deletion.
What does the loudness checker measure?
It measures the complete primary audio stream for integrated LUFS, true peak and loudness range, builds a short-term timeline, and reports long silence, possible clipping and notable left/right imbalance.
Is minus 14 LUFS an official YouTube requirement?
No. The minus 14 LUFS, minus 1 dBTP WoluTools preset is a transparent processing default, not an official YouTube upload limit or compliance target. Custom targets remain visible and confirmed.
Does the tool re-encode my video?
When fixing an MP4 or MOV, the primary video stream is copied where the output container permits it. Only the primary audio stream is processed to AAC at 48 kHz. Measure-only mode changes no media.
What is Even out spoken voice?
It applies gentle deterministic compression before two-pass loudness normalisation. It can reduce large level swings in dialogue, but it does not remove noise, repair distortion or replace a proper mix.
Can I hear the change first?
Yes. The analysis creates a short original and recommended M4A preview. Both expire with the two-hour review draft and are never part of the public landing-page demo.
Which files are supported?
Version 1 accepts MP4 and MOV video up to 4 GB and 120 minutes, or MP3, WAV, M4A, FLAC and OGG audio up to 500 MB and 180 minutes. The primary audio stream is used.
What is included in the package?
The ZIP contains an accessible HTML analysis, second-by-second timeline CSV, processing manifest and, unless Measure only was chosen, a fixed MP4, M4A, WAV or both selected audio formats.
When are files deleted?
An unfinished encrypted upload and its listening previews expire after two hours. Source parts and previews are removed after completion, failure or cancellation. The encrypted result expires after 24 hours or immediately when deleted.
Available now
Inspect the measurement before sharing real media.
The synthetic demo is open. Your own files run here without an account: 3 free jobs a day, or up to 200 a day with Pro.