Subtitle workflow for filmmakers
Subtitles are usually one of the last things a filmmaker thinks about and one of the first things they regret if it goes wrong. This guide is about the practical workflow — when to subtitle, what to expect at each stage and how to avoid the most common production problems.
When to start subtitling
You should not start subtitling until picture lock. If the edit is still changing, subtitles will have to be redone. Many productions subtitle the rough cut for festival submissions and then re-time after final delivery.
That said, you can prepare certain things before picture lock:
- Translate the script. The translation can be done before the edit is final.
- Spot dialogue. Identify which lines need subtitles and which don't (for example, inaudible background chatter might not need subtitles).
- Prepare the subtitle file structure. Have your workflow ready to go so subtitling is fast when you reach picture lock.
The subtitle production stages
1. Transcription
Produce a transcript of all dialogue. This is the base for the subtitle file. Transcription is easiest from the final audio mix, but if the mix is not ready, transcribe from the scratch mix and adjust.
2. Spotting
Spotting is marking when each line of dialogue begins and ends in the timeline. This is where the subtitle timing is born. Some productions do spotting manually (frame accurate) and some use automation (ASR with human correction).
For films, spotting is usually done with specialized subtitle software (EZTitles, Subtitle Edit, or built-in tools in DaVinci Resolve and Avid). For lower-budget work, tools like the ones on this site can handle many steps.
3. Translation
If the film is being subtitled into another language, translation happens after the source subtitle is done. The translator works cue by cue, respecting timing and line length.
4. QC (Quality Control)
QC checks the subtitle file for:
- Timing accuracy — does each cue appear when the actor says the line?
- Reading speed — can the audience read the cue in the time available?
- Line length — do lines fit in the 42-character rule?
- Spelling and grammar.
- Consistency — character names, terminology.
- Formatting — italics for voice-over, brackets for sound effects if SDH.
QC is usually done by a second person. Reading your own subtitles is unreliable — you know what they are supposed to say.
5. Delivery
Deliver the subtitle file in the format the distributor requires:
- Streaming platforms — SRT, WebVTT, or their proprietary format (Netflix for example has its own TTML-based format).
- Film festivals — usually SRT or a burned-in version.
- Broadcast — depends on the network; often STL or proprietary.
- Cinema — usually burned in or delivered via DCP subtitle stream (XML-based).
- Web — WebVTT.
Specialist deliverables
- SDH (Subtitles for the Deaf and Hard of Hearing) — for streaming and broadcast, SDH includes sound effects and speaker labels.
- Forced narrative subtitles — for scenes in another language within a primarily English film. These are burned in or displayed on top of the primary track.
- Descriptive subtitles — subtitles that describe visual action for blind audiences (usually delivered as audio description, not text).
Timing precision in film
Film subtitles are timed to the frame, not to the millisecond. At 24 fps, each frame is 41.67ms. Subtitle start and end times should align to frame boundaries. Most subtitle software handles this automatically, but it matters for delivery — some broadcasters reject files that are not frame-accurate.
Common production pitfalls
- Subtitling before picture lock. Wasted effort when the edit changes.
- Not validating files. Broken files get caught in QC, delaying delivery.
- Inconsistent style across scenes. Italics, speaker labels and formatting should follow a style guide.
- Missing languages. Producers forget to commission subtitle translations for territories that need them.
- Delivery format mismatch. Delivering SRT when the client needs STL means reprocessing.
- Uncorrected ASR. Auto-generated subtitles are almost never acceptable for professional delivery.
Low-budget workflow
If you are a solo filmmaker on a tight budget:
- Transcribe the film manually or with an ASR tool.
- Time the subtitle file in a free subtitle editor (Subtitle Edit or Aegisub).
- Translate if needed, using a translation memory tool or manual translation.
- Validate with the SRT Validator.
- Check line length with the Line Length Checker.
- Convert to the delivery format with the appropriate converter (e.g. SRT to VTT).
Related tools
- SRT Validator
- Duration Report
- Line Length Checker
- SRT to VTT
- Subtitle Merger for combining split subtitle tracks.