01Phase 01
1. Cue Parsing & Timestamp Alignment
Import standard .srt or .vtt subtitle files or analyze speech intervals. The engine parses start/end timecodes, cue text, and positional attributes into structured subtitle objects.
Word-Level Timestamps · SRT & WebVTT
Auto Subtitle Generator & Audio to Text Sync
Synchronize and export audio to text subtitle tracks (WebVTT and SubRip .srt) with millisecond-accurate timestamps and automatic cut realignment for video and podcast creators.
Auto Subtitle Generator & Audio to Text Sync
Ready for a local audio or video file
Local Browser Audio Engine
Scanning speech & quiet pauses…
Reading media and computing RMS energy…
1Reading file
2Decoding audio
3Scanning quiet
4Building map
Loudness:-16.0 LUFS
Peak:-1.0 dBFS
0:00 savedPacing Preset
Speech cushionsFine-tune detection parameters
Balanced
Balanced (~-38dB): Calibrated natural balance recommended for podcasts, YouTube videos, and dialogue.
0.80s
0.20s (all micro-pauses)2.50s (only long pauses)
0.32s
0.00s (flush / jump)0.80s (spacious)
Automatically removes silence before first speech and after last speech.
Pause #01✂️ Cut Proposed
00:14.2 → 00:16.8 (2.6s gap)
1.6s quiet gap; keeps 0.32s breathing room.
Tip: Press Del or Backspace to cut selected silenceR to keep
Silence Map (0)
0 silences found (0.0s dead air) · 0 will be cut, 0 kept
Target ScopeAll Clips
All edits reversible
Studio DSP & Ambience Rack
Real-Time DSP✨
1-Click Full Background Noise Removal
Removes 80Hz rumble, 50/60Hz hum, room hiss & mouth clicks
Anti-Blackout
Fills shortened silence gaps with authentic room tone synthesized from your recording, eliminating unnatural "vacuum dropouts".
Butterworth
-40 dBFS
+2.5dB Clarity
Sibilance
Cubic Spline
-1.0 dBFS
Subtitle Range Protection
Protect Intentional Sentences & Pauses
Importing your subtitle transcript locks dialogue boundaries so dramatic reflections and deliberate speech pauses inside sentences are never auto-cut.
No subtitles loaded
Hesitation Splicer (Fillers & Stutters)
Removes verbal hesitation sounds (um, uh, er, like) and repeated stutters.
0 fillers0 stutters
Merged with acoustic cuts
A/V Dual-System Sync
Drift ConformerEdit Evidence & Provenance
Manifest v1.0Total Proposals
0
Active Cuts
0
Restored Pauses
0
Protected Lines
0
Structural Export Validation:
✔ Zero server uploads (100% Client-Side)
✔ True-Peak Limiter ceiling ≤ -1.0 dBFS
✔ Duration conservation verified (Δ ≤ 5ms)
✔ 8ms anti-click zero-crossing micro-fades
Media Preflight & Capabilities
Source Format:Audio Track
Sample Rate:44.1 kHz
Channels:Stereo (2-ch)
Memory Footprint:~12 MB RAM
Local Processing:100% Client-Side
Verified Export Options:
- ✔ 16-Bit PCM WAV: Uncompressed lossless master audio.
- ✔ Audacity Labels: Drag-and-drop label track for Audacity / Reaper.
- ✔ CSV Cue Sheet: Tabular marker list with exact timestamps.
- ✔ EDL / FCPXML: Timeline cut lists: EDL for Premiere & Resolve, FCPXML for Final Cut & Resolve.
- ✔ Evidence Manifest: JSON & CSV audit trail with a CRC-32 source checksum.
Episode Show Notes
Silence #01 detected (00:04.4 → 00:05.0)
🎬Sequence Track1 clip
Pause Map & Timeline
Click / drag to scrub0:000:00
✨
✨ Cleaning Noise...Background Noise Remover
Multi-band spectral Wiener filtering & room rumble removal
Strong (75%)
0% (Off)50% (Balanced)100% (Studio Max)
Space Play/Pause · Del Trim · R Keep · J/L Jump 2sDouble-click waveform to trim
Lossless 16-Bit Master Audio & Edit Ledger Export
Rendered locally in browser memory with 8ms anti-click micro-fades. Zero server upload.
Detected from video
Chain in Studio FlowTimeline files reference your media by file name only. Final Cut Pro, DaVinci Resolve or Premiere Pro will ask you to relink the clip to the original file.
✨ Hover any tool icon to see what it does · Click to launch
100% browser-local processing · No files uploaded to any server
Acoustic Engineering Guide · Architecture
How this tool works in browser memory
How this tool decodes, analyzes, and masters your dialogue locally with zero cloud latency.
02Phase 02
2. Waveform Mapping & Sentence Protection
Syncs subtitle cue ranges across the interactive waveform. Active sentence intervals are locked as protected dialogue, preventing intentional reflective pauses from being deleted.
03Phase 03
3. Resynchronized Subtitle Export
Whenever pauses or filler words are trimmed, all subsequent subtitle cue timecodes are automatically recalculated and exported as standard WebVTT or SubRip (.srt) files.
Connected finishing workflows
Explore companion utilities for dialogue cleanup, speech pacing, and mastering.
Text-Based Video Editor
Edit video pacing and splice cuts directly by reading transcript cues.
Filler Words & Stutter Detector
Review hesitation crutches and stutters with word-level precision.
Podcast Show Notes Generator
Generate structured Markdown episode notes and timestamped chapters.
Audio Standards & Research
Engineering guides & deep-dive workflows
Explore the acoustic principles, ITU-R loudness standards, and pacing techniques behind this tool.
Subtitles6 min read
How to Use Imported SRT or VTT Captions to Review Spoken-Word Edits
How text-audio alignment works: importing SRT/VTT files, protecting enclosed pauses within sentences, and exporting synchronized subtitles.
Subtitle Sync7 min read
How to Keep Subtitles in Sync After Cutting Silence and Dead Air
The mathematics of cumulative cue timecode offsetting: recalculating WebVTT/SRT start and end timestamps proportionally across trimmed pause intervals.
Text-Based Editing8 min read
Text-Based Video Editing Workflow: How to Cut Video by Editing Words
How text-based timeline engines map subtitle tokens to video frame boundaries, preserve sentence structures, and export NLE timelines.
Frequently Asked Questions
Common Questions & Technical Clarifications
How to transcribe audio to text online and sync subtitles?+
To transcribe audio to text and sync subtitles online: 1. Import your audio or video file into the workspace. 2. Load your transcript or generate timestamped subtitle cues directly in browser memory. 3. Review word tokens and trim dead air with sentence protection, then export synchronized W3C-compliant WebVTT (.vtt) or SubRip (.srt) subtitle tracks.
What happens to subtitle timestamps when I cut silences or dead air?+
When you shorten a quiet gap or remove a filler word, AutoSilenceCut calculates the exact time duration removed and dynamically shifts all subsequent subtitle cues forward. When you export, your new .srt or .vtt file stays in frame-accurate synchronization with your edited audio and video.
What is subtitle sentence protection?+
Traditional silence removers often cut natural pauses between words or dramatic pauses inside spoken sentences. Subtitle sentence protection uses imported transcript cue boundaries to recognize active dialogue sentences and automatically locks them, ensuring intentional pauses are preserved.
What subtitle formats can I import and export?+
You can import standard SubRip (.srt) and WebVTT (.vtt) formats. You can export updated WebVTT files with exact W3C-standard millisecond timestamps, formatted SRT files, Audacity label tracks (.txt), or CSV edit ledgers.
Are my audio tracks or subtitle transcripts uploaded to any third-party servers?+
No. AutoSilenceCut operates 100% locally on your computer. Your media files and subtitle text are processed entirely within browser memory and are never uploaded to any remote server or AI cloud.