Powered by WhisperX AI

Convert Audio to Subtitles with AI in Seconds

Upload an audio or video file — get transcript JSON, SRT, TXT and TikTok-style .ASS subtitles ready to use instantly

Free 5,000 creditsNo credit card requiredStarting from $2.99No monthly subscription
Try Free — 5,000 CreditsView Pricing

Features

High-Accuracy Transcription

Uses WhisperX with word-level timestamps for precise alignment

TikTok-Style ASS Subtitles

Generate word-by-word or pause-split subtitles in portrait or landscape

15+ Languages Supported

Thai, English, Chinese, Japanese, Korean and more with Auto-detect

Fast, Pay-Per-Use

No monthly subscription — buy credits and pay by actual minutes used

Align Mode

Already have a script? Let AI match timestamps to your audio without changing words

Multiple Export Formats

Download as JSON, SRT, TXT or ASS — all jobs saved in your Dashboard

FAQ

Frequently Asked Questions

Everything you need to know about FastCaption

FastCaption is an AI-powered subtitle and caption generator. Upload any audio or video file and get accurate transcriptions with word-level timestamps in seconds. Export as SRT, ASS (TikTok-style), JSON, or plain text. Start free with 5,000 credits — no credit card required.

Yes! Every new account gets 5,000 free credits (approximately 25 minutes of transcription). No credit card required. After that, credit packs start at just $2.99 — no monthly subscription needed.

FastCaption uses WhisperX, one of the most advanced speech recognition engines, with word-level forced alignment. Expect 95%+ accuracy for clear audio in supported languages.

FastCaption supports 15+ languages including English, Thai, Japanese, Korean, Chinese, Spanish, French, German, Portuguese, Italian, Dutch, Russian, Arabic, Hindi, Vietnamese, and Indonesian. Language auto-detection is also available.

SRT (universal format for YouTube, Premiere Pro, etc.), ASS (with TikTok-style word-by-word highlighting), JSON (with word-level timestamps), and plain TXT transcripts.

Absolutely! FastCaption generates ASS subtitle files with trendy word-by-word highlighting effects. Choose portrait (9:16) orientation, download the ASS file, and import into CapCut, Premiere Pro, or any video editor.

Sign up and get 5,000 credits free!

≈ 25 minutes of transcription — no credit card required

Starting from $2.99 · No subscription · Credits never expire

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