# CALM Act Commercial Loudness Checker

Check whether a commercial is louder than the programme it accompanies, per the FCC CALM Act rules and ATSC A/85: compare average loudness, grade the excess on the A/85 listener comfort scale, and flag loud-opening “gaming” with momentary-loudness diagnostics.

> Canonical page: https://elysiatools.com/en/tools/audio-calm-act-checker

- **Category:** Media

- **Keywords:** calm act, commercial loudness, atsc a/85, lkfs, lufs, loud commercials, fcc, broadcast, tv advertising, anchor loudness, dialnorm, bs.1770, -24 lkfs, true peak

## Overview

The US CALM Act (enacted 15 December 2010, FCC rules effective 13 December 2012) requires TV commercials to be transmitted no louder than the programme material they accompany; the FCC rules incorporate ATSC A/85 by reference, whose core requirement is that the average loudness of a commercial must not exceed the average loudness of the surrounding programming. This checker measures both files the way the standard does: ITU-R BS.1770-4 K-weighted integrated loudness with the two-stage EBU Mode gate, taken over the full duration including all channels except LFE (A/85 Annex J.4). For long-form programmes A/85 anchors on the dialogue element; this tool measures the full-program mix, so for cinematic mixes you can instead enter the known anchor or dialnorm value directly. The loudness difference is graded on the A/85 Annex E listener tolerance scale: +2.4 dB is louder-but-acceptable, +5.6 dB makes viewers reach for the volume control, +10.8 dB is annoyingly loud, while a commercial up to +2 dB over the programme sits inside the A/85 measurement tolerance. True peak of the commercial is checked against the A/85 −2.0 dBTP limit, and because the FCC’s 2025 review highlights commercials that “game” the average with an exceptionally loud opening, the maximum momentary (400 ms) loudness of the commercial is compared with the programme’s as an informational diagnostic. Files are only read, never modified.

## Inputs

- **Programme audio** (file)
- **Programme loudness source** (select)
- **Programme anchor loudness (LKFS)** (number): e.g. -24
- **Commercial audio** (file)

## When to use

- Before delivering commercial audio spots to US broadcast stations or cable networks.
- During quality control to verify true peak limits and ITU-R BS.1770-4 integrated loudness compliance.
- When diagnosing listener comfort scale excess or potential loud-opening average gaming.

## How it works

- Upload the commercial audio file and provide the accompanying programme audio file or enter a known programme anchor loudness in LKFS.
- The tool calculates the ITU-R BS.1770-4 K-weighted integrated loudness using EBU Mode gating across all channels except LFE.
- It measures the maximum true peak against the ATSC A/85 -2.0 dBTP limit and compares momentary loudness to identify abrupt spikes.
- A compliance report generates a loudness difference metric, Annex E comfort scale rating, and true peak verification.

## Use cases

- Broadcast delivery verification for agency audio mixers preparing 30-second broadcast spots.
- Network ingestion QC to prevent FCC rule violations across sponsor ad reels.
- Comparative loudness analysis for dynamic commercial intros against television programme dialogue anchors.

## Frequently asked questions

### What standard does this checker use for loudness calculation?

It uses ITU-R BS.1770-4 K-weighted integrated loudness with two-stage EBU Mode gating, adhering to ATSC A/85 Annex J.4.

### What is the maximum allowed true peak under ATSC A/85?

ATSC A/85 establishes a true peak ceiling of -2.0 dBTP for commercial content.

### Can I check a commercial without uploading the full programme file?

Yes, switch the programme source option to manual and input your dialnorm or target anchor value in LKFS.

### Does this tool alter or re-encode my source audio files?

No, files are processed strictly in read-only mode to measure acoustic parameters without modifying the audio data.

### What is considered an acceptable loudness difference between commercial and programme?

A commercial sitting within +2.0 dB of the programme anchor falls inside standard ATSC A/85 measurement tolerance.

## Related tools

- [Audio CD Red Book Checker](https://elysiatools.com/en/tools/audio-cd-red-book-checker): Check album tracks against the Red Book CD-DA standard: 44.1 kHz / 16-bit / stereo PCM, sample peaks, 4-second minimum tracks, 99-track limit, and disc capacity in sectors.
- [Codec Artifact Detector](https://elysiatools.com/en/tools/audio-codec-artifact-detector): Compare an original master with its lossy encode and flag pre-echo, transient smearing, bandwidth loss and stereo damage, with per-event timestamps.
- [Podcast RSS Enclosure Checker](https://elysiatools.com/en/tools/audio-podcast-rss-enclosure-checker): Validate podcast episode audio against hosting expectations and cross-check it with your RSS feed: enclosure URL / length / type attributes, itunes:duration, GUID uniqueness, RFC 2822 dates, platform codecs and bitrates — byte-exact enclosure lengths included.
- [Audio Caption Sync Checker](https://elysiatools.com/en/tools/audio-caption-sync-checker): Compare SRT or WebVTT cue timing with likely speech activity and flag timing drift.
- [Audio Dictation Quality Checker](https://elysiatools.com/en/tools/audio-dictation-quality-checker): Check whether audio is suitable for transcription using SNR, clipping, format, channels, and speech activity.
- [Audio Mix Translation Checker](https://elysiatools.com/en/tools/audio-mix-translation-checker): Simulate your mix on phone, laptop, earbud, car, club, mono and noisy-street playback, export every render in a ZIP, and report what survives each system.
- [Audio Platform Delivery Checker](https://elysiatools.com/en/tools/audio-platform-delivery-checker): Check podcast or spoken-audio files against platform delivery profiles, including codec, loudness, metadata, chapters, cover art, and decodability.
- [ATSC A/85 Broadcast Loudness Validator](https://elysiatools.com/en/tools/audio-atsc-a85-validator): Validate audio against ATSC A/85 (CALM Act): -24 LKFS ± 2 LU program loudness per ITU-R BS.1770-4, -2.0 dBTP oversampled true peak, 48 kHz delivery check and a dialnorm cross-check, with a per-file short-term timeline chart.

## Samples

- [Copyright-Free FLAC Audio Samples](https://elysiatools.com/en/samples/flac-samples): Lossless FLAC audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music
- [Copyright-Free MP3 Audio Samples](https://elysiatools.com/en/samples/mp3-samples): Collection of royalty-free audio samples for testing and development purposes including nature sounds, meditation music, and ambient audio
- [Copyright-Free WAV Audio Samples](https://elysiatools.com/en/samples/wav-samples): Uncompressed PCM WAV audio samples for testing and development, mirrored from MP3 set with nature sounds and meditation music
- [Copyright-Free Raw PCM Audio Samples](https://elysiatools.com/en/samples/pcm-samples): Raw PCM s16le audio samples featuring nature ambience and relaxing music for waveform, playback, and conversion workflows