AI Captions & Subtitles

Captions have become essential. Social feeds autoplay muted. Accessibility matters. And styled captions are now a design element. AI makes captioning fast and (mostly) painless.

Why Captions Matter

The Statistics

• 85% of Facebook videos are watched without sound
• 80% of viewers are more likely to watch to completion with captions
• Captions improve SEO (searchable text)
• Required for accessibility compliance in many contexts

Types of Captions

Closed Captions (CC):

• Separate file (SRT, VTT)
• Viewer can toggle on/off
• Platform displays them
• Editable after upload

Open Captions (Burned-in):

• Part of the video file
• Always visible
• More design control
• Can't be turned off

Subtitles:

• Translation to other languages
• Same formats as CC
• Often styled differently

AI Captioning Tools

Built-In Platform Tools

Platform	Quality	Features
YouTube	Excellent	Auto-generate, easy edit
TikTok	Good	Auto-generate
Instagram	Good	Auto-generate
LinkedIn	Good	Auto-generate

Dedicated Tools

Tool	Strength	Price
CapCut	Styled captions	Free
Descript	Accuracy + editing	$12/month
VEED	Browser-based	Free tier
Kapwing	Collaboration	Free tier
Rev	Human + AI hybrid	$0.25/min

The Captioning Workflow

Step 1: Generate Transcript

Upload video to your tool of choice. AI transcribes:

Accuracy factors:

• Clear audio = better results
• Single speaker = better than multiple
• Standard accent = better accuracy
• Technical terms = often wrong

Step 2: Review and Edit

Always review! Common errors:

• Homophones (their/there/they're)
• Proper nouns (names, brands)
• Technical terms
• Numbers and dates
• Unclear speech sections

Efficient review process:

1. Read through while playing video
2. Fix obvious errors
3. Check technical terms specifically
4. Verify speaker labels (if multiple)

Step 3: Timing Adjustment

Auto-generated timing is usually good, but check:

• Words appearing too early/late
• Captions that stay too long
• Awkward line breaks

Most tools let you:

• Drag caption timing
• Split long captions
• Merge short ones
• Adjust globally

Step 4: Styling

For burned-in captions, styling matters:

Font choices:

• Sans-serif for clarity
• Bold for impact
• Avoid decorative fonts

Color strategy:

• High contrast with video
• White with black outline (universal)
• Brand colors if consistent background

Size:

• Large enough to read on mobile
• Not so large it blocks content
• 6-8% of frame height typical

Position:

• Bottom third (traditional)
• Center (modern social media style)
• Top (if bottom is occupied)

Step 5: Export

Export options:

SRT/VTT file:

• Upload separately to platform
• Viewer can toggle
• Can be translated
• Editable post-upload

Burned-in:

• Part of video file
• Maximum design control
• Works everywhere
• Can't be modified

Caption Styles for Social Media

The "Trending" Style

Popular on TikTok and Reels:

• Center position
• Large, bold text
• Animated appearance (word by word or bounce)
• Color changes on key words
• Emoji integration
• 3-4 words max per screen

The "Professional" Style

For LinkedIn, YouTube, corporate:

• Bottom position
• Clean, readable font
• White text, black background bar
• Full sentences visible
• Minimal animation

The "Minimal" Style

Subtle, doesn't distract:

• Small, bottom corner
• Semi-transparent background
• Simple font
• No animations

CapCut Caption Walkthrough

Step-by-step for styled captions:

1. Import video

2. Generate captions:

   • Text → Auto captions
   • Select language
   • Wait for processing

3. Review transcript:

   • Click any caption to edit
   • Fix errors

4. Apply template:

   • Click caption on timeline
   • Choose style template
   • "Apply to all" for consistency

5. Customize style:

   • Font, size, color
   • Background/outline
   • Animation type
   • Position

6. Fine-tune timing:

   • Adjust individual captions
   • Ensure sync with speech

7. Export:

   • Choose resolution
   • Captions are burned in

Multi-Language Captions

Reach global audiences:

Translation Workflow

Option 1: AI Translation

1. Generate captions in original language
2. Use AI to translate (DeepL, Google Translate)
3. Have native speaker review
4. Create separate SRT for each language

Option 2: Professional Translation

1. Export transcript
2. Send to translation service
3. Import translated SRT files
4. More accurate, more expensive

Option 3: Platform Auto-Translate YouTube, TikTok offer auto-translation. Quality varies.

Upload Multiple Languages

Most platforms support multiple caption tracks:

video.mp4
├── captions_en.srt (English)
├── captions_es.srt (Spanish)
├── captions_pt.srt (Portuguese)
└── captions_de.srt (German)

Viewers select their preferred language.

Accessibility Considerations

Beyond Basic Captions

True accessibility includes:

• Speaker identification: "[John] So what I think..."
• Sound descriptions: "[door slams]", "[upbeat music]"
• Tone indicators: "[sarcastically]", "[whispers]"
• Non-speech audio: "[phone ringing]", "[crowd cheering]"

Caption Quality Checklist

• 99%+ accuracy (professional standard)
• Proper punctuation and grammar
• Speaker labels when multiple people
• Sound effects described
• Timing synced with speech
• Readable font and contrast
• Appropriate reading speed

Common Mistakes to Avoid

Over-styling: Animations and colors shouldn't distract from content

Ignoring review: AI makes mistakes. Always check.

Wrong timing: Captions that lag or lead are frustrating

Too much text: Break long sentences into shorter captions

Poor contrast: White text on bright background = unreadable

Tiny font: Mobile viewers need to read too

Tools Comparison

Feature	CapCut	Descript	VEED	YouTube
Auto-generate	Yes	Yes	Yes	Yes
Style templates	Many	Few	Some	None
Animation	Yes	Limited	Yes	No
Multi-language	Manual	Manual	Yes	Auto
Export SRT	Yes	Yes	Yes	Yes
Price	Free	$12/mo	Free tier	Free

Key Takeaway

AI captioning saves hours of manual work. Generate transcripts automatically, but always review for errors. Style your captions to match your content type—animated and bold for social media, clean and professional for business content. And remember: captions aren't just nice to have—they're essential for reach, engagement, and accessibility. In the next module, we'll explore AI avatars and virtual presenters.