Apps & Tools

Caption Burn-In Studio

Hardcode SRT or VTT subtitles directly into your video frames, 100% in-browser with zero uploads.

100% Private & Client-Side: Your video and subtitles are processed entirely inside your web browser using HTML5 Canvas and MediaRecorder. Nothing is uploaded to any cloud server.

1. Import Video & Captions

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Select Video File

MP4, WebM, MOV, or MKV

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Select Subtitle File

.SRT or .VTT format

Or Paste Subtitle Text (SRT Format):

2. Live Preview & Styling Controls

00:00 / 00:00

Font Family

Font Size

Text Color

Background Box / Pill

Vertical Position

Text Case

3. Render & Download Hardcoded Video

Click below to render the video frame-by-frame with burned-in subtitles. Rendering runs at high speed in real time inside your browser memory.

Container & Video Format

Preparing render pipeline...

Knowledge Base

Hardcoded Captions vs. Soft Subtitles

Hardcoded (burned-in) captions are drawn directly onto the video frames during rendering. Unlike soft subtitles (which require an external SRT file or player toggle), burned-in captions display universally on any device, social media platform, or video player without relying on platform support.

When to Use Hardcoded Captions

Social Media Short-Form (Reels, TikTok, Shorts): Mobile users frequently watch videos on mute. Burned-in captions ensure 100% viewer retention.
Digital Signage & Kiosks: Displays running silent loops rely on visible text rendered on the frame.
Universal Web Playback: Guarantees custom fonts and brand colors display identically across iOS, Android, Windows, and Mac.

Subtitle Formatting Best Practices

Safe Zone Margins: Keep bottom captions elevated 10 to 12% above the lower frame boundary to prevent overlapping with platform UI elements (like TikTok sound titles or video progress bars).
Contrast & Legibility: Always use a dark background pill box or thick text stroke when rendering captions over dynamic background footage.

FAQ

Q: Is my video uploaded to any server?
A: No. All video decoding, canvas drawing, subtitle rendering, and video recording take place 100% inside your local browser memory.

Q: What subtitle formats are supported?
A: Supports standard .SRT (SubRip) and .VTT (WebVTT) subtitle files, as well as direct text pasting.