Select an audio file, choose CBR, VBR or ABR, and encode locally in your browser using a standalone WebAssembly LAME 3.100 MP3 encoder. Advanced users can add ID3 tags, cover art, output names and a technical conversion log.
Common browser-readable audio and video files can be converted locally. Very large files may be limited by browser memory.
Encoder note: this web page uses a standalone patched LAME 3.100 WebAssembly bridge. It exposes CBR, LAME VBR quality and ABR target bitrate modes in the browser, including Xing/LAME VBR headers for correct duration reporting in typical players. In VBR mode, V0–V9 is the main quality control rather than a bitrate target. The experimental cVBR and cVBRb branch features remain available in the downloadable Windows command-line builds. Read the cVBR comparison.
The quick menu covers common choices. In VBR mode, the V0–V9 quality value is the main control and a bitrate target is not required. ABR and CBR use the bitrate field. For modern LAME VBR, algorithm-quality values 0–4 use the highest internal VBR analysis path, so the VBR quality value is usually the setting that matters.
ID3 tags are written locally in the browser after encoding. Smaller cover images are recommended to avoid unnecessarily large MP3 files.
Ready.
This tool converts supported audio and video files to MP3 directly in your browser. It uses a WebAssembly encoder based on stable LAME 3.100 and currently exposes bitrate-based MP3 output. Your selected file is processed locally on your device and is not uploaded to lamemp3.co.uk.
The web encoder is intended for quick, convenient MP3 creation. For true LAME -V VBR control, cVBR, cVBRb, command-line use, batch encoding, and experimental branch features, use the downloadable Windows builds.
Use the Online MP3 Encoder for local browser conversion with CBR, VBR and ABR modes. Use the Windows command-line builds if you need cVBR, cVBRb, bitrate boost, batch processing, scripting, or exact command-line control.
The conversion runs locally in your browser. Your selected media file is not uploaded to this website.
The online encoder uses a standalone patched LAME 3.100 WebAssembly bridge. It exposes CBR, VBR quality and ABR target bitrate modes, plus optional algorithm-quality and filter controls. cVBR and cVBRb branch features remain in the downloadable Windows builds.
Use Advanced Options for VBR/ABR/CBR settings, ID3 tags, cover art, filename choices and the technical conversion log. For batch work, command-line automation, cVBR and cVBRb encoding, use the Windows builds.
The online encoder uses the same LAME encoder core compiled to WebAssembly. For a small DeltaWave-based check against the Windows command-line builds, see the comparison notes.