Audio loudness tool

CALM Act Loudness Checker -24 LUFS

Analyze audio loudness locally in your browser and compare it with the common ATSC A/85 CALM Act target of -24 LKFS/LUFS.

Upload Audio or Video

Drop an audio/video file or choose one from your device.

Generic CALM Act Audio Loudness Check

The CALM Act points U.S. TV commercial loudness practice toward ATSC A/85, where a common target is -24 LKFS. This tool helps creators, editors, advertisers, and QA teams quickly spot commercials or program audio that may be too loud or too quiet before final delivery.

Important: This tool is not an official legal determination and is not affiliated with the FCC, ATSC, or any broadcaster. Use it for browser-based preflight estimates only.

What it reports

Integrated LUFS, loudness range estimate, sample peak, channel count, duration, target difference, and suggested gain adjustment.

How to use the result

If the file is outside the target range, apply the suggested gain in your editor or loudness normalizer, then export and check again.

CALM Act Loudness FAQ

Short answers for -24 LUFS/LKFS loudness estimates and audio delivery prep.

What loudness target does the CALM Act use?

For U.S. broadcast delivery, the common ATSC A/85 target is -24 LKFS, which is equivalent to LUFS for practical loudness reporting.

What target range should I use?

Many workflows use -24 LKFS with a typical tolerance of plus or minus 2 LU. This checker marks audio from -26 to -22 LUFS as within a practical target range.

Does this replace an official or certified broadcast loudness meter?

No. This browser tool gives a practical local estimate for editing and QA. It is not affiliated with the FCC, ATSC, or any broadcaster. Final delivery should be checked with an approved meter and your delivery specification.

Are uploaded audio files sent to a server?

No. The browser decodes and analyzes the file locally with the Web Audio API. The file does not need to be uploaded for the loudness check.