Build Live Caption Broadcasting for Events with Next.js and Elevenlabs API



This content originally appeared on DEV Community and was authored by jQueryScript

captions.events: Open-source real-time captioning platform for live events

Built with Next.js, ElevenLabs Scribe v2, and Supabase Realtime.

Features:

🎤 100-200ms transcription latency with automatic language detection

🌍 On-device translation into 14+ languages using Chrome’s built-in AI

📡 Broadcast to unlimited viewers through Supabase Realtime

🔒 Single-use token system keeps API credentials secure

📜 Full caption history with language metadata

👤 GitHub OAuth for authentication and event management

All translation happens locally in the viewer’s browser. No external API calls, no privacy concerns, works offline after initial model download.

Perfect for conferences, webinars, presentations, or any event needing accessible multilingual captions.

👉 Blog Post

👉 GitHub Repo

👉 Live Demo


This content originally appeared on DEV Community and was authored by jQueryScript