flowsub.ai

Introduction to flowsub.ai

flowsub.ai is an AI-powered subtitle generation service that converts audio and video content into accurate, timestamped subtitles. It leverages OpenAI Whisper to deliver studio-quality output in minutes, supporting creators who need accessible, multilingual, and production-ready captions without manual transcription.

The service is designed for podcasters, educators, marketers, and content creators across platforms. By automating caption generation and translation, flowsub.ai helps improve accessibility, discoverability, and global reach—particularly for audiences who consume video without sound or in non-native languages.

Key Takeaways

• Generates accurate, timestamped subtitles and closed captions from any video or audio file
• Supports 99+ languages with automatic language detection
• Exports subtitles in SRT, VTT, TXT, and ASS formats
• Free tier includes 10 minutes of transcription per month, no credit card required
• Pro tier adds unlimited transcription, subtitle translation, burn-in video preview, and advanced format support (VTT, ASS)
• Accepts common media formats: MP4, MKV, MOV, AVI, WebM (video); MP3, WAV, M4A, OGG (audio)
• Maximum file size: 500 MB
• Built on OpenAI Whisper for high transcription accuracy on clear audio

How flowsub.ai Works

Users begin by uploading a supported video or audio file through the web interface. The system processes the audio using OpenAI Whisper, which transcribes speech and assigns precise timestamps to each segment. The resulting transcript is formatted as synchronized subtitles with speaker-agnostic segmentation.

After processing—which typically completes within 1–3 minutes—users can review the generated subtitles in-browser and download them in their preferred format: SRT (widely compatible), VTT (web standard), TXT (plain text), or ASS (advanced styling, Pro only). Pro users may also translate subtitles into any supported language and preview or export videos with burned-in captions.

Core Benefits and Applications

Podcasters use flowsub.ai to convert episodes into searchable, shareable transcripts—enhancing SEO and enabling clip-based social distribution. Educators apply it to make lectures and course materials accessible via auto-generated captions, fulfilling accessibility standards efficiently. Social media creators benefit from increased engagement, as subtitled videos perform better in muted feed environments. Global teams and multilingual publishers leverage the translation feature to localize content rapidly, distributing a single video asset across diverse linguistic audiences while maintaining timing integrity and formatting fidelity.