Ultimate Guide to Subtitle Compliance: FCC, EBU, Netflix & SDH Standards

In the digital media era, subtitles are no longer just an optional convenience for viewers scrolling on mute. They are a fundamental pillar of video accessibility, user experience, and legal compliance. Whether you are delivering a film to Netflix, broadcasting a television program in Europe, or publishing an educational series on YouTube, your content must conform to specific regulatory and industry specifications.

Failing to comply with these standards can result in rejected deliverables, legal liabilities under accessibility acts, or poor viewer retention. In this guide, we break down the four most critical global subtitling standards—FCC Part 79, EBU Tech 3384, Netflix Delivery Specs, and Accessible SDH—and explain how you can easily implement them.

1. FCC Closed Captioning (Part 79) – The US Legal Requirement

If you distribute video programming in the United States, compliance with the Federal Communications Commission (FCC) rules under Part 79 is mandatory for television and online media that previously aired on TV.

The FCC evaluates closed caption quality based on four core metrics:

• Accuracy: Captions must match the spoken words in the dialogue to the fullest extent possible. This includes preserving slang, dialect nuances, and non-speech sounds (like background laughter or door slams).
• Synchronicity: Captions must appear at the exact moment the dialogue or sound occurs and must remain on screen long enough to be read naturally.
• Completeness: Captions must run from the very beginning to the very end of the video program without gaps.
• Placement: Captions must be positioned on screen so they do not block critical visual elements, such as speaker faces, on-screen graphics, or main credits.

2. EBU Tech 3384 – The European Broadcasting Standard

The European Broadcasting Union (EBU) established the EBU Tech 3384 specifications to define the subtitling standard for broadcasters and media outlets across Europe. The focus of this standard is clear readability and reducing cognitive load for viewers.

Key formatting rules include:

• Line Constraints: Subtitles are limited to a maximum of 2 lines per card. Single-line cards are preferred whenever possible.
• Character Limits: Each line should not exceed 37 to 42 characters for Latin-based alphabets.
• Reading Speed: Pacing must be kept between 12 and 16 characters per second (CPS). Exceeding this speed makes the subtitles disappear too quickly, rendering them unreadable.
• Timing Intervals: A subtitle card must stay on screen for a minimum of 1 second and a maximum of 7 seconds. A gap of 2 to 4 frames must be left between consecutive cards to allow the viewer's eyes to register the transition.

3. Netflix Subtitle Specifications – The Streaming Gold Standard

As the pioneer of global subscription video-on-demand (SVOD), Netflix developed its own highly detailed subtitle delivery specifications. Today, these specifications are widely recognized as the gold standard for streaming content.

Critical Netflix rules include:

• Line Length: A hard limit of 37 characters per line for Latin-based languages, rendered in a center-aligned sans-serif font.
• Semantic Line Breaks: Line breaks must occur at natural semantic units. Do not split a name, an adjective from its noun, or an auxiliary verb from its main verb across lines.
• Line Balance: Subtitle lines should be balanced. The upper line should generally be equal to or shorter than the lower line (forming an inverted pyramid shape) to avoid blocking the video composition.
• Speaker Identification: Use parentheses or square brackets to identify off-screen speakers if their identity is not visually apparent, e.g., (Narrator) or [John].

4. Accessible Subtitling & SDH Standards – Subtitles for the Deaf and Hard-of-Hearing

Subtitles for the Deaf and Hard-of-Hearing (SDH) go beyond standard dialogue translation by incorporating non-speech elements to offer complete audio accessibility.

Guidelines for premium SDH subtitles include:

• Sound Descriptions: Background noises, sound effects, off-screen actions, and musical cues must be described inside brackets, e.g., [car horn honks] or [upbeat pop music plays].
• Speaker Identification: Prefix the subtitle text with the speaker name in uppercase or brackets when the speaker is off-screen or multiple people are speaking, e.g., NARRATOR: ... or [Sarah]: Hello!.
• Atmosphere and Vocal Cues: Describe the emotional delivery or vocal tone when it is critical to the story progression, e.g., [whispering quietly] or [screams in panic].

How to Meet Compliance Standards Instantly

Manually adjusting every subtitle card to ensure it doesn't exceed character limits, conforms to reading speeds, and breaks at semantic units is incredibly tedious. That's why we built SRTGen.

In our professional workspace, you can easily apply preset formatting limits (such as forcing a 37-character limit or checking reading speed). Furthermore, for projects requiring certified precision, you can request our Human QA Review option. Our team of compliance-certified subtitlers will review your video to guarantee it meets FCC, EBU, Netflix, or SDH guidelines perfectly.

Ensure your videos are accessible, professional, and compliant. Check out the SRTGen Workspace to start editing today!