Vous m'avez trouvé sur Upwork ? Si vous m'avez trouvé via Upwork et souhaitez faire appel à mes services, merci de me contacter via Upwork. Les messages de clients Upwork envoyés en dehors d'Upwork ne recevront pas de réponse.
Notes de localisation🎬 Sous-titrage

How to Fix YouTube Auto-Captions and Re-Upload a Clean SRT

YouTube auto-captions come with duplicate rolling cues and wrong names. Download with yt-dlp, fix in Subtitle Edit, and re-upload a corrected SRT in YouTube Studio.

Dao Huy (Lucas)6 min read8 sections
How to Fix YouTube Auto-Captions and Re-Upload a Clean SRT

💡 YouTube auto-captions come with duplicate rolling cues, missing punctuation, and wrong proper nouns. Download the track using yt-dlp --write-auto-subs --convert-subs srt --skip-download, load into Subtitle Edit, run Remove duplicate rolling captions and Fix common errors (overlapping times on), then re-upload the corrected SRT in YouTube Studio under Subtitles > Upload file > With timing.

Key takeaways

  • --write-auto-subs --convert-subs srt --skip-download fetches the auto-caption track as a clean SRT without re-downloading the video.
  • The biggest defect in exported YouTube auto-captions is the rolling-window cue overlap: Subtitle Edit's "Remove duplicate rolling captions" collapses them automatically.
  • Run Fix common errors with "Fix overlapping display times" and "Remove empty lines" enabled before every re-upload.
  • Upload the corrected file in YouTube Studio as "With timing" SRT; YouTube adds it as a reviewed track alongside the auto-generated one - then delete the auto-generated track.
  • Proper nouns, missing sound-effect labels, and lines over 42 characters still need a manual check after the automated pass.

What makes YouTube auto-captions inaccurate?

I work with caption files every day, and YouTube's auto-generated track has the same four problems every time I clean one up.

First, the rolling-window export. YouTube streams captions in overlapping 3-4 second windows that share 10-15 words with the previous cue. When you export the raw auto-caption file, each cue contains words from the prior cue too, so three consecutive cues all share the same central phrase. The file looks like a caption file but reads like a transcript cut at random boundaries.

Second, proper nouns are unpredictable. Names, brands, technical terms, and any speaker with a regional accent get mangled. A video about "Subtitle Edit by Nikse" may come back as "Subtitle at it by Nick" in the auto-caption.

Third, punctuation is sparse. Auto-captions add periods at major sentence breaks but miss commas inside long clauses, leaving the viewer to parse a wall of text.

Fourth, there is no non-speech information. No sound-effect labels like [Music], no speaker IDs, no [Applause] cues. For a hearing-impaired viewer those gaps fall short of SDH standard.

Downloading your own auto-captions with yt-dlp

yt-dlp is the command-line tool I use to pull the auto-caption track from my own video without re-downloading the full file. Three flags drive this workflow: --write-auto-subs targets the auto-generated track (not any manually uploaded subtitle), --convert-subs srt converts the raw VTT output to SRT so Subtitle Edit loads it cleanly, and --skip-download skips the video itself.

# Download auto-captions from your own YouTube video (caption file only)
yt-dlp \
  --write-auto-subs \
  --sub-langs "en" \
  --sub-format "vtt/best" \
  --convert-subs srt \
  --skip-download \
  "https://www.youtube.com/watch?v=VIDEO_ID"
  • --write-auto-subs: requests the auto-generated caption track, not a manually uploaded subtitle file.
  • --sub-langs "en": fetches English only; use all to pull every available language at once.
  • --sub-format "vtt/best": prefers VTT from YouTube's API and falls back to the best available format.
  • --convert-subs srt: converts VTT to SRT on the way out, so you get a clean file Subtitle Edit loads without extra steps.
  • --skip-download: skips the video entirely - you only need the caption file.

The output lands in the current directory as VIDEO_TITLE.en.srt. Open it in any text editor and the rolling-cue problem is immediately visible: the first three cues will share most of their words.

How do I clean up duplicate rolling lines?

This step takes the most time in a typical YouTube auto-caption cleanup. Open the SRT in Subtitle Edit and work through this pass in order:

Subtitle Edit cleanup pass for YouTube auto-captions
----------------------------------------------------
1. Tools > Fix common errors
   Enable: Fix overlapping display times
   Enable: Remove empty lines
   Enable: Fix short display times (min 800 ms)
   Run.

2. Tools > Remove duplicate rolling captions
   (Detects the rolling-window overlap pattern and merges the cues)

3. Edit > Find & Replace
   Fix wrong proper nouns, brand names, speaker names.

4. Select cues shorter than 2 words > merge or delete manually.

5. Tools > Fix common errors (second pass, same settings) > Run.

6. File > Save As > SubRip (.srt)
  • Fix overlapping display times: nudges the end time of each cue back so it does not overlap the start of the next one. Essential before upload.
  • Remove duplicate rolling captions: Subtitle Edit detects the overlapping-text pattern from YouTube's rolling-window export and merges consecutive cues that share text into single clean cues. On a 10-minute video this typically collapses 80+ rolling cues down to 25-35 clean ones.
  • Second pass: the first merge sometimes leaves very short residual cues. Running Fix common errors again catches those leftovers.

After this automated pass, scan every line for names and technical terms. The tools above cannot fix transcription errors - that part still needs a human eye.

The auto-caption defect checklist

Here are the seven defect types I check in every YouTube auto-caption cleanup, and how I address each one:

Defect typeExampleFix method
Duplicate rolling cues"hello how are" / "how are you" / "are you doing"Remove duplicate rolling captions (Subtitle Edit)
Wrong proper noun"Dao Hoy" for "Dao Huy"Edit > Find & Replace
Overlapping timestampsCue 1 ends 00:01:02,500; Cue 2 starts 00:01:02,400Fix common errors > Fix overlapping times
Missing punctuationRun-on clause with no comma breakManual scan; Find & Replace patterns
Cue too shortDuration 120 ms, 1 wordFix short display times (min 800 ms)
Missing sound-effect label[Music] absent on intro/outroAdd manually
Line too longSingle line 60+ charactersSplit at a natural phrase break

Is re-uploading the cleaned file enough for accessibility compliance?

For a standard YouTube video aimed at a general audience, a cleaned SRT - merged rolling cues, corrected timing, obvious transcription errors fixed - is a meaningful step up from the raw auto-caption. For most creators that is the right outcome: viewers can follow the content, captions stay on time, and YouTube marks the track as reviewed.

There are cases where the automated cleanup is not enough, and a professionally produced deliverable is worth it:

  • Medical, legal, or technical content where a wrong term changes the meaning. Auto-captions mishear drug names and legal terms; a human reading the screen can catch those errors.
  • ADA or Section 508 compliance for a US federal agency or educational institution. WCAG 1.2.2 and Section 508 require captions that accurately represent all audio content, including non-speech sounds and speaker IDs. A cleaned SRT usually satisfies this for general content, but a human review is the safe path for regulated material.
  • Content where your brand or product name is consistently mis-transcribed. Viewers notice this.
  • SDH (Subtitles for the Deaf and Hard of Hearing) for a broadcast or streaming deliverable. SDH adds sound effects, music cues, and speaker IDs in a specific format that auto-captions never produce without a manual pass.

If you need a fully correct English caption or SDH track for professional distribution, my creator and short-form captioning service covers the full pipeline from raw auto-caption to a clean re-uploadable file. The SDH service goes further for broadcast-standard deliverables that carry sound-effect labels and speaker IDs.

FAQ

Can I use yt-dlp to download auto-captions from someone else's video?

Technically yes - yt-dlp can download public auto-captions from any public YouTube video using the same flags. This article focuses on fixing and re-uploading to your own channel. Downloading another creator's captions to redistribute raises copyright concerns, and you cannot upload them to a channel you do not own. Use this workflow only on your own content.

Will removing duplicate rolling cues lose any words?

No. Subtitle Edit's "Remove duplicate rolling captions" detects the overlapping-text pattern and collapses consecutive cues that share text into single merged cues, keeping all unique words. Always play through the result in Subtitle Edit's video preview after the merge to confirm nothing was dropped.

Does this workflow apply to YouTube Shorts auto-captions?

Yes, the same yt-dlp command works for Shorts. YouTube Shorts uses the same ASR system and exports in the same rolling-window VTT format. The Subtitle Edit cleanup pass is identical. The main difference is duration: a 60-second Short typically produces 10-15 clean cues after the merge, so the pass is faster.

What CPS limit should I target after cleanup?

For a general English-speaking YouTube audience I aim for a maximum of 20 characters per second (CPS) per cue. That aligns with the conservative end of the Netflix Timed Text Style Guide for English and is a comfortable reading pace. Subtitle Edit shows CPS per cue in the waveform bar; anything marked red exceeds the limit. Set the threshold at Edit > Settings > General > Maximum characters per second.

Does YouTube replace the auto-generated track when I upload a corrected SRT?

No - uploading a corrected SRT adds a new reviewed subtitle track alongside the existing auto-generated one; it does not overwrite it. After uploading, go to Subtitles in YouTube Studio, find the auto-generated track, click the three-dot menu, and select Delete to remove it so viewers only see your corrected version.

Official Sources

Dao Huy (Lucas)
Dao Huy (Lucas)
Diplômé de l'Université des langues étrangères, Université de Da Nang. Signe une attestation d'exactitude sur chaque traduction certifiée (USCIS, IRCC).

Écrit par Đào Huy (Lucas), traducteur vietnamien et spécialiste de la localisation (anglais, chinois et français vers le vietnamien). See translation services →

DevisWhatsApp