Audio Bitrate Changer
Change audio bitrate to optimize file size or quality. Lower bitrate means smaller files.
Bitrate Changer
Drop audio files here or
Maximum file size: 50MB • Files: 0 / 1
Accepted format: audio files
Download Converted Audio
No Audio Files Yet
Upload and change audio bitrate to see them appear here for download.
Change the bitrate of MP3 and AAC audio files in your browser to optimize file size versus quality. Choose from 64, 96, 128, 192, or 320 kbps — no uploads, instant processing with FFmpeg WebAssembly.
Audio Bitrate Changer for MP3 and AAC File Size Optimization
Audio bitrate directly controls the trade-off between file size and audio quality. A 320 kbps MP3 is considered transparent quality (indistinguishable from lossless for most listeners), while 128 kbps is standard streaming quality, and 64 kbps is suited for speech-only content where bandwidth is limited.
Our browser-based audio bitrate changer uses FFmpeg WebAssembly to re-encode your audio file at a target bitrate of your choice. This is useful for reducing file sizes before uploading to a streaming platform, email attachment limits, or mobile app distribution — and for standardizing bitrate across a library of files for consistent streaming performance.
Common bitrate use cases: podcast distribution platforms (Spotify, Apple Podcasts) recommend 128 kbps stereo for music and 96 kbps mono for speech; YouTube accepts up to 320 kbps; mobile apps benefit from 128 kbps to balance storage and quality. Understanding the file-size impact: a 3-minute song at 320 kbps is approximately 7.2 MB, while the same file at 128 kbps is approximately 2.8 MB.
Real-Time File Size Estimation Before Converting
Before you convert, the tool displays an estimated output file size based on the target bitrate and audio duration. This helps you make an informed decision — for example, comparing 192 kbps versus 128 kbps to see if the 30% quality gain justifies the larger file size. The estimate uses the formula: file size (MB) = (bitrate kbps × duration seconds) ÷ 8000, which is accurate to within a few percent for CBR (constant bitrate) encoding.
Podcast and Streaming Platform Optimization
Re-encode podcast episodes to the recommended bitrate for Spotify (128 kbps stereo) or Apple Podcasts (96 kbps mono) to meet platform guidelines while minimizing file size.
Mobile App Audio Asset Reduction
Reduce in-app audio file sizes by lowering bitrate on background music and sound effects to decrease app download size without perceptible quality loss.
Audio Library Standardization
Normalize a library of audio files from mixed bitrates to a single consistent bitrate for uniform streaming performance and predictable storage costs.
- 1
Upload Your Audio File
Select or drag and drop an MP3, AAC, M4A, OGG, or WAV file. The file loads into browser memory — nothing is sent to any server.
- 2
Select Target Bitrate
Choose your desired output bitrate from the preset options: 64, 96, 128, 192, or 320 kbps. Review the estimated output file size displayed next to each option.
- 3
Convert and Download
Click Convert. FFmpeg WASM re-encodes the audio at the selected bitrate. Download the output file in the same format as the input (or choose MP3/AAC output).
Multiple Bitrate Presets
Choose from 64, 96, 128, 192, or 320 kbps presets covering the full range from speech-optimized bandwidth savings to high-fidelity near-lossless quality.
Real-Time File Size Estimation
See the estimated output file size before converting, based on target bitrate and audio duration, helping you choose the optimal bitrate for your use case.
MP3 and AAC Output
Re-encode to industry-standard MP3 or AAC formats, both widely supported across streaming platforms, devices, browsers, and operating systems.
Browser-Only Processing
FFmpeg WASM handles all encoding in your browser tab with no server uploads, no account creation, and no file size restrictions beyond your device RAM.
Found this tool useful?
Share your experience and help others discover it.