Subtitle Batch Processing Guide

Introduction

When working with multiple subtitle files — an entire season of a TV show, a course with dozens of lectures, or a library of films — processing files one by one is painfully slow. Batch processing lets you apply the same operation to all files simultaneously, turning hours of work into seconds.

When You Need Batch Processing

TV Series

Apply the same timing offset to all 10-24 episodes of a season when the source video has consistent sync issues.

Course Content

Convert all lecture subtitle files from SRT to VTT for your web-based learning platform.

Media Libraries

Clean formatting tags from hundreds of subtitle files downloaded from various sources.

Localization Workflows

Prepare subtitle files for translation by stripping tags and cleaning duplicates across an entire project.

Available Batch Operations

1. Time Shifting

Apply a millisecond offset to all subtitle timings across every file. Positive values delay subtitles; negative values make them appear earlier.

Use case: An entire season's subtitles are consistently 500ms early — shift all files by +500 in one go.

2. Format Conversion

Convert all files from SRT to VTT or VTT to SRT. The tool handles timing format differences (commas vs periods) automatically.

Use case: Your media server requires VTT but all your files are SRT.

3. Tag Removal

Strip HTML tags, ASS override codes, and bracket content from all files. Empty entries created by cleaning are automatically removed.

Use case: You downloaded subtitles with SDH markers and formatting tags that you don't need.

4. Empty Entry Removal

Remove subtitle entries that contain no text across all files. Remaining entries are re-indexed.

Use case: After OCR extraction, many files have blank entries that cause timing gaps.

5. Duplicate Removal

Remove entries with identical text within each file. For more advanced similarity detection, use our dedicated Duplicate Remover.

Use case: Auto-generated captions with repeated entries across multiple video files.

How to Use

1. Select files — use Ctrl+Click or Cmd+Click to pick multiple files
2. Choose operation — select from the dropdown menu
3. Configure parameters — set shift amount, target format, etc.
4. Process — click the button and watch the progress bar
5. Download — grab files individually or download all at once

Tips for Efficient Batch Processing

• Start with a test — process one file first to verify the settings are correct
• Mix formats freely — you can load both SRT and VTT files in the same batch
• Check results — spot-check a few files after batch processing
• Chain operations — run one batch operation, then load the results for another

Privacy & Security

All processing happens in your browser. Files are never uploaded to any server. This means:

• No file size limits
• No waiting for server processing
• Complete privacy for sensitive content
• Works offline after the page loads

Try our Free Batch Processor today!