Is this converter free?

Yes, WebConverter is completely free to use. There are no hidden fees, no subscription plans, and no limits on the number of files you can convert.

Do my files get uploaded to a server?

No. All conversions happen entirely in your browser using WebAssembly. Your files never leave your device, ensuring complete privacy and security.

What formats are supported?

This converter supports the following formats: MP3, WAV, OGG, MP4, M4A, WebM, FLAC.

Can I use this offline?

Yes! WebConverter works as a Progressive Web App. Once installed, you can convert files without an internet connection.

Are there file size limits?

No, there are no artificial file size limits. The only limit is your device's available memory and processing power.

Transcribe Audio

AI-powered audio transcription — drop your audio file and get a text transcript. Free, private, no upload.

Need to transcribe a recording, podcast, or voice memo? Drop your audio file and get a full text transcript with timestamps. Uses OpenAI's Whisper model running locally via WebAssembly — your audio never leaves your device.

MP3WAVM4AOGGFLACWebMMP4

Choose your spoken language and quality, then download the model. It runs entirely in your browser and is cached for next time.

Spoken language Quality

High quality is more accurate and uses a larger one-time download. Normal works well for clear speech; for some languages such as Chinese, High is noticeably better.

Drop an audio file here or click to browse

Supports MP3, WAV, M4A, OGG, FLAC, WebM, MP4

Transcript

Include timestamps

You saved about 0 kg CO₂ compared to using other online converters.
No data transfer — all data stays on your device!

AI Audio Transcription in Your Browser

This tool uses the Whisper speech recognition model compiled to WebAssembly. Choose your language and quality, then download the model once (about 24 MB for Normal, about 41 MB for High). It is cached for future visits. Audio files are decoded in your browser using the Web Audio API, then processed by the AI model to produce a timestamped transcript. Supports MP3, WAV, M4A, OGG, FLAC, WebM, and more.

Features

Near-Zero CO₂

Server-based converters upload your file, process it remotely, and send it back — consuming network and data-centre energy on every request. WebConverter runs entirely on your device, so the only energy used is your local CPU. No data transfer, no server electricity.

Install for Offline Use

WebConverter works offline as a Progressive Web App. Click "Add to Home Screen" on mobile or the install button in your browser's address bar. Once installed, you can convert files without any internet connection.