Free Video to SRT Converter - AI Subtitle Generator (OpenAI Whisper · Offline)
100% free video to SRT converter powered by OpenAI Whisper and WebGPU running entirely in your browser. Transcribe MP4, MOV, WebM videos with millisecond-accurate timestamps and export editor-ready .srt and .vtt subtitles without file upload.
Drag and drop video here, or click to browse files
Supports MP4, MOV, WebM, MKV, AVI, FLV formats (Supports 4K & large files)
Open Source AI Architecture & Evidence
This tool is powered entirely by the most authoritative open-source speech recognition and on-device inference engines. All code runs transparently in your browser.
Trained on 680,000 hours of multilingual audio, Whisper provides industry-standard timestamp alignment, automatic punctuation, and speech segmentation.
github.com/openai/whisperExecutes ONNX models directly inside browser workers with WebGPU and WebAssembly hardware acceleration, without external server dependencies.
github.com/huggingface/transformers.jsLoads official INT8 and FP32 quantized weights with permanent browser caching via Cache/IndexedDB for instant offline reuse.
huggingface.co/onnx-communityWhether you load a 100MB clip or a 10GB 4K file, media decoding happens inside local memory. Verify zero network uploads anytime in DevTools (F12).
✓ 100% In-Browser Memory DemuxWhy Choose Our Video to SRT Subtitle Generator?
Traditional subtitle tools require uploading multi-gigabyte video files to cloud servers, risking sensitive footage and wasting hours on slow bandwidth. Our tool transforms the workflow:
Zero Video Uploads, Instant Demuxing
Extracts the 16kHz audio track directly from MP4/MOV video containers in browser memory with zero network delay.
Millisecond-Accurate Subtitle Timestamps
Generates standard 00:00:01,234 --> 00:00:04,567 timecodes ready for Premiere Pro, CapCut, DaVinci Resolve, and Final Cut Pro.
In-Browser WebGPU GPU Acceleration
Utilizes your device GPU (Nvidia/AMD/Apple Silicon) for 5x-10x faster local inference.
100% Free with No Limits
No video length limits, no file count limits, no watermarks, and no subscription walls.
How to Convert Video to SRT and Import into Video Editors
Drop Video File
Drag any MP4, MOV, or WebM video into the dropzone or load a sample test.
Select Language & Generate
Choose the spoken language (or auto-detect) and click Generate SRT Subtitles.
Download & Drag into Premiere / CapCut
Click Download .SRT and drag the file directly onto your editing timeline.
Video to SRT Troubleshooting & Best Practices
What if a long 4K video slows down transcription?
We recommend Whisper Tiny or Base models for instant results. The tool only reads the audio stream, keeping memory footprint lightweight.
How to fix garbled subtitle text in video editors?
Our tool exports clean UTF-8 encoded SRT files. If legacy software misinterprets encoding, open the SRT in a text editor and re-save as UTF-8.
Can I edit subtitle text before downloading?
Yes, you can edit text in the visual timeline or raw SRT editor before clicking download.
Video to SRT Frequently Asked Questions (FAQ)
What is an SRT subtitle file?
SRT (SubRip Text) is the most widely used subtitle format worldwide, containing sequential numbers, start/end timestamps (hours:minutes:seconds,milliseconds), and text.
Is video data uploaded to any remote server?
No! All processing is executed locally inside your browser via WebGPU and WebAssembly. Your videos never leave your computer.
Which video editing software supports these SRT files?
100% compatible with Adobe Premiere Pro, CapCut, DaVinci Resolve, Final Cut Pro, Sony Vegas, and all standard media players (VLC, QuickTime).
Does it work offline?
Yes! Once the model is cached upon first launch, you can generate subtitles completely offline without internet access.