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Elephant Audio
Audio production · Sound design · Music production
LahorePKEngineering sound since 2018
All delivery specs
Territory reference
ATSC A/85 — US Television Loudness
What loudness does US television require?
ATSC A/85 recommends a Target Loudness of −24 LKFS for US television content delivered without metadata, with true peak no higher than −2 dBTP. Long-form programmes are measured on their dialogue; short-form content such as adverts is measured on the full programme mix. A tolerance of about ±2 dB is anticipated, but content should not be aimed at either edge.
Source
Transcribed from the published standard, read 2026-09-24. Check it yourself
−24 LKFS
Target Loudness
content without metadata
−2 dBTP
maximum true peak
±0.5 dB meter tolerance anticipated
Dialogue
long-form anchor
short-form uses the full mix
±2 dB
measurement tolerance
not a window to aim within
One target, two ways of measuring it
A/85 defines what is measured, not just the number. For long-form content — programmes — the loudness is the average dialogue level, measured with BS.1770-1 (without the relative gate added in later revisions) together with a dialogue-gating algorithm, over the entire duration of the composite mix rather than act by act.
For short-form content — adverts, promos, interstitials — the loudness is the full-programme mix, measured with ITU-R BS.1770-3 or later. The full-programme mix is not to be used for long-form content except in the rare case that it contains no dialogue at all.
The quick reference, as written
From Table M.1 of A/85:2026-07, Annex M:
- Long form: integrated dialogue loudness −24 LKFS without metadata; with metadata, dialnorm equals the loudness. Maximum true peak −2 dBTP.
- Short form: full-program mix loudness −24 LKFS without metadata; with metadata, dialnorm equals the loudness. Maximum true peak −2 dBTP.
- For delivery or exchange without metadata, and with no prior arrangement between the parties, the Target Loudness should be −24 LKFS.
- Content should be presented at one specific and consistent Target Loudness; where that is not possible, short-form content should not be louder than the long-form content it accompanies.
⚠️ The ±2 dB is a measurement tolerance, not a target window
Annex M anticipates a measurement tolerance of up to approximately ±2 dB around −24 LKFS, due to measurement variations — and states in the same breath that content loudness should not be targeted to the high or low side of it. Mixing to −22.5 because it is “inside the tolerance” uses up the margin meant for meter disagreement.
True peak carries its own allowance: a minor tolerance of up to approximately ±0.5 dB is anticipated because meters vary. The ceiling itself is −2 dBTP, which the 2013 edition explains as headroom against clipping in downstream processing such as audio coding.
Streaming is treated separately
For streaming delivery services only, Annex M recommends a single Target Loudness between −23 and −27 LKFS, unless the parties have agreed otherwise. It notes that some streaming operators use −23 LKFS, conformant to EBU R 128 s2, some use −27 LKFS for greater headroom, and some use −24 LKFS as the default in the absence of any other agreed value.
Sources
- ATSC A/85:2026-07 — Annex M, Loudness and True Peak Quick Reference (PDF)— Table M.1 and footnotes 30–35. Every figure here. Read 2026-09-24.
- ATSC — A/85 document page— The standard's home on atsc.org, with the current revision.
- ATSC A/85:2013 — Techniques for Establishing and Maintaining Audio Loudness (PDF)— The earlier edition; source of the −2 dB TP headroom rationale.
Common questions
Is ATSC A/85's −24 LKFS the same as EBU R 128's −23 LUFS?
The unit is the same — LKFS and LUFS are both ITU-R BS.1770 loudness — but the targets differ by one decibel, and the measurement differs too: US long-form content is measured on dialogue, while EBU R 128 measures the whole programme with the level gate. A file tuned for one is not automatically compliant with the other.
How is the loudness of a US television programme measured?
On its dialogue. A/85 says the average dialogue level must be measured and reported as the loudness of long-form content, using BS.1770-1 without the relative gate plus a dialogue-gating algorithm, over the whole programme. The full mix is used only for content with no dialogue at all.
What true-peak level does ATSC A/85 allow?
A maximum of −2 dBTP for both long-form and short-form content. Annex M anticipates a minor measurement tolerance of about ±0.5 dB because meters vary, and the earlier edition explains the headroom as protection against clipping in downstream audio coding.
Does ATSC A/85 require −24 LKFS for streaming?
No. For streaming delivery services only, Annex M recommends a single Target Loudness somewhere between −23 and −27 LKFS unless the parties agree otherwise, and notes that operators differ within that range.
Next
- Check a US advert's loudness and true peak
- The measurement ATSC and the EBU both use
- The European target, one decibel apart
- Which target applies to your spot
- Mixing and mastering to a delivery target
This page is the lookup. Broadcast and Streaming Loudness Specs for Commercials is the explanation behind it.
Delivering to US television?
Long-form is judged on dialogue and short-form on the full mix, so the same stems can pass one way and fail the other. We measure each deliverable the way the network will.
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