Encode supported PCM WAV as real MP3 with selectable 128, 192, 256 or 320 kbps quality.
Drag and drop one or more files, or choose files from your device.
Supported: .wav · up to 5 sources · 50 MiB per source. Existing codec, duration, pixel and memory limits apply.
Existing native decoding, codec, bitrate, channel/sample-rate policy, clipping-headroom and independent audio verification. Jobs remain sequential with the original decoder/encoder cleanup.
Enter your values locally; no inputs are uploaded.
Check validation feedback before reviewing the browser-generated result.
Review the explanation, copy supported outputs or reset the workspace.
Choose a supported local file, review its detected codec and stream information, adjust settings, convert and play or inspect the verified output before downloading.
Encode supported PCM WAV as real MP3 with selectable 128, 192, 256 or 320 kbps quality. Measured conversion progress, bounded processing, cancellation, local previews and output codec checks support a practical private workflow.
Files, filenames and media data stay in browser memory. There are no conversion uploads, external conversion APIs, source-content analytics or storage persistence. Downloads require an explicit action; reset/unmount revokes owned media URLs and closes processing resources. Source metadata tags are not copied.
The verified subset is mono/stereo PCM 8-, 16-, 24- or 32-bit WAV and IEEE float32 WAV within the shown limits. Compressed ADPCM, unsupported extensible layouts, incomplete frames and other WAV codecs are rejected.
Choose 128, 192, 256 or 320 kbps, with 192 kbps as the default. The local LAME encoder generates constant-bitrate audio frames, and the resulting frame headers are checked against the selected setting.
No. MP3 is perceptually lossy at every offered bitrate. A higher bitrate generally reduces compression artifacts and increases file size, without guaranteeing that the original PCM samples can be recovered exactly.
Original mono/stereo and MPEG-1 rates of 32, 44.1 and 48 kHz are retained. Other supported input rates are explicitly resampled to a compatible rate for the selected bitrate range, with a warning.
Decoded samples are checked for invalid values and signal levels. Headroom attenuation is applied and disclosed when needed; output is decoded again and rejected if duration, clipping or unexpected-silence checks fail. Intentional silent sources remain valid.
MP3 frame boundaries, encoder/decoder priming and padding can add roughly a tenth of a second. Metadata frames and headers also affect average file size/bitrate; the selected CBR is checked on actual audio frames rather than the Xing metadata frame.
Encode supported PCM WAV as real MP3 with selectable 128, 192, 256 or 320 kbps quality.
The verified subset is mono/stereo PCM 8-, 16-, 24- or 32-bit WAV and IEEE float32 WAV within the shown limits. Compressed ADPCM, unsupported extensible layouts, incomplete frames and other WAV codecs are rejected.
Native browser decoding and local LAME MP3 encoding are used where applicable. MP3 is lossy; PCM output retains the intended decoded samples subject to chosen transformations/quantization. Codec priming and frame padding can affect duration by about 0.1 seconds.
Media engines load on demand when a file is processed. LAME encoding uses a small bundled WASM extension; no FFmpeg engine is downloaded by the application. Inputs are bounded to 50 MiB and supported streams to 180 seconds. Measured progress, cancellation, output decoding and previews help verify real results. Source files and filenames are not uploaded, logged or persisted.