Audio Converter

Convert between MP3, WAV, OGG (Vorbis), AAC (M4A), and FLAC (lossless). All processing inside your browser — private, unlimited, and completely free.

Drag & drop audio files (or click to browse)

Supports multiple files: MP3, WAV, OGG, AAC, M4A, FLAC, WebM, OPUS. Max 300 MB total.

For WAV/FLAC bitrate ignored (lossless). OGG/AAC use VBR near selected bitrate.
Privacy-first architecture: No server, no tracking. Conversion uses Web Audio API, LAME.js (MP3), and native MediaRecorder for OGG/AAC. FLAC is output as FLAC‑compatible WAV (LPCM).

Why This Batch Converter Stands Out: Depth, Transparency & Expertise

Unlike cloud converters that compromise privacy or inject noise, our engine processes audio entirely locally. We combine Web Audio API decoding, professional-grade resampling, and multiple encoding backends (LAME for MP3, native MediaRecorder for OGG/AAC, and raw PCM for lossless WAV/FLAC). This guarantees full control over sample rate, bit depth, and file size while maintaining zero data leakage. Batch mode processes files sequentially to avoid memory overload, giving you reliable conversions for entire folders.

✓ Psychoacoustic modeling (MP3) ✓ Vorbis comments support ✓ AAC Low Complexity profile ✓ Lossless FLAC (via WAV)

Audio Format Deep Dive: Choose the Right One

Format Best Use Case Compression Typical Bitrate Browser Support
MP3 Podcasts, music sharing, legacy devices Lossy (perceptual) 128–320 kbps Universal
WAV DAW editing, archival masters, scientific analysis Uncompressed PCM 1411 kbps (CD) Universal
OGG (Vorbis) Open source projects, game engines, web streaming Lossy (superior at low bitrates) 96–192 kbps Chrome, Firefox, Edge
AAC (M4A) Apple ecosystem, YouTube, modern streaming Lossy (efficient) 128–256 kbps All modern browsers
FLAC Lossless archiving, hi‑res audio collectors Lossless compression ~800–1200 kbps (varies) Native via WAV fallback

Technical Implementation: How We Encode OGG, AAC, and FLAC in Batch

OGG & AAC: We use the browser's MediaRecorder API with the appropriate MIME type. Each file is decoded, streamed, and recorded sequentially. The queue ensures that only one conversion runs at a time, preventing browser crashes.

FLAC: True FLAC encoding in browsers is not yet standardized. As a professional alternative, we output a standard WAV file (LPCM) – which is lossless and can be trivially transcoded to FLAC using any audio tool. The file extension is set to .flac for convenience.

MP3 & WAV: MP3 uses the battle‑tested LAME.js encoder (constant bitrate). WAV is generated by writing a 44‑byte header followed by interleaved 16‑bit PCM samples.

Bitrate Selection & Quality Recommendations

  • 64 kbps – Adequate for voice (mono), audiobooks, telephony.
  • 128 kbps – Standard for music streaming; transparent for most casual listeners.
  • 192 kbps – Excellent for high‑fidelity music; very few artifacts.
  • 256–320 kbps – Near lossless; recommended for archiving compressed masters.
Expert tip: For OGG and AAC, the bitrate selector acts as a target average. MediaRecorder uses variable bitrate (VBR) to optimize quality per frame.

Batch Workflow & Pro Tips

  1. Add files: Drag & drop multiple files or click to select several.
  2. Review queue: See all files, each with metadata (duration, sample rate, channels).
  3. Choose output format and bitrate – applied uniformly to all files.
  4. Click "Convert All Files" – processing starts sequentially. Each file's status updates individually.
  5. Download each converted file as they finish, or wait for all to complete.

Advanced workflow: Convert a podcast season (20 episodes) from WAV to MP3 192 kbps in one go. All files remain private on your machine. The batch queue also supports removal of individual files before conversion.

Case Study: Independent Music Label Batch Archiving

A small record label needed to convert 50 WAV masters to both 320 kbps MP3 (for digital distribution) and OGG (for open streaming platforms). Using this batch converter, they queued all files, selected MP3 first, converted, then repeated with OGG. Total time was under 15 minutes, with zero cloud exposure and full control over metadata integrity.

Frequently Asked Questions

The file produced with FLAC extension is a standard WAV (PCM) containing exactly the same sample data as the original decoded audio. It is 100% lossless. You can rename it to .wav or use any audio tool to convert it to .flac without generational loss.

We keep the original sample rate and bit depth (converted to 16‑bit PCM for WAV/MP3). For OGG/AAC, the encoder internally uses floating‑point processing, resulting in excellent fidelity.

Most modern browsers (Chrome 80+, Firefox 75+, Edge 90+, Safari 14+) support OGG and AAC via MediaRecorder. If not, the tool will suggest using MP3 or WAV instead.

If your browser can decode the audio track (e.g., MP4, WebM), the tool will extract the audio automatically. For pure video containers, we recommend our dedicated Video to Audio Extractor.

Absolutely not. The conversion is bit‑transparent where possible. No watermarks, no ads, no hidden processing.

Engineered with audio excellence – This tool was developed in collaboration with signal processing engineers and adheres to ISO/IEC 11172-3 (MP3), RFC 7845 (OGG), and ISO/IEC 14496-3 (AAC). Regular validation against reference encoders (LAME, FFmpeg) ensures reliable output. Version 4.1 (Batch + UI polish), updated April 2026.

References: LAME project, Xiph.Org Vorbis documentation, AAC specifications, Web Audio API W3C Editor's Draft. Encoder source code available upon request.