Audio Format Converter

Convert audio files between formats directly in your browser. Supports MP3, FLAC, WAV, M4A, Opus, and OGG Vorbis. All processing is local — your files never leave your device.

Key features

How to use

Drop or select an audio file, choose the output format and quality, then click Convert. The conversion runs entirely in your browser using WebAssembly.

About quality settings

Low, Medium, and High refer to bitrate presets (128, 192, 320 kbps) for lossy formats. Lossless preserves the original quality. For lossless-to-lossless conversion (e.g. WAV to FLAC), quality does not affect the output.

Important: MP3 to FLAC does not improve quality

Converting a lossy format (like MP3) to a lossless format (like FLAC) does not restore lost audio data. It only re-encodes the existing lossy audio in a lossless container. The result will sound identical to the original MP3, but the file size will be larger.

Common use cases

Convert MP3, FLAC, WAV, M4A, Opus, and OGG locally

Change audio formats in the browser for sharing, device compatibility, podcast clips, or personal library cleanup without uploading the file.

Create smaller lossy copies from lossless files

Convert FLAC or WAV to MP3, M4A, Opus, or OGG when you need a smaller file for a phone, car player, or web upload.

Avoid false quality upgrades

The tool warns that MP3 to FLAC does not improve sound quality, so you can choose a format based on compatibility rather than fake lossless claims.

Frequently asked questions

What formats are supported?

Input: any audio file your browser can read (MP3, FLAC, WAV, M4A, OGG, OPUS, etc.). Output: MP3, FLAC, WAV, M4A (AAC), Opus, OGG Vorbis.

Is my audio file uploaded to a server?

No. The conversion runs entirely in your browser using WebAssembly. Your audio file never leaves your device.

Can converting MP3 to FLAC improve audio quality?

No. MP3 is a lossy format — some audio data has already been discarded. Converting to FLAC just stores the lossy audio in a larger file without restoring any quality.

Why is the conversion engine loading?

The first conversion requires loading the WebAssembly engine (~25 MB). This is cached by your browser for subsequent use.

Is there a file size limit?

There is no hard limit, but very large files (>100 MB) may be slow or fail due to browser memory constraints. For heavy batch processing, use a desktop tool like FFmpeg or OFPlayer Toolkit.

Can I convert multiple files at once?

This web tool processes one file at a time. For batch conversion, use OFPlayer Toolkit (desktop) or the FFmpeg command line.

About this page

Audio Format Converter is part of OFPlayer's local-first music workflow. The page is designed to explain the feature, tool, or guide in plain language before you open the interactive app experience.

OFPlayer focuses on personal music collections, browser-based utility tools, WebDAV and Subsonic/Navidrome workflows, privacy-first playback, and lightweight library management. Files stay under your control, and the website avoids account-based lock-in.

Useful next pages from here include Audio Metadata Viewer、Audio Spectrum Viewer、Loudness Scanner / ReplayGain、GitHub. These internal links help you continue from overview, to setup, to actual playback or tool usage without losing context.