Make a lower-bitrate copy
Change a 320 kbps MP3 to 128 or 192 kbps when you want to use less storage. Compare speech, quiet passages and music detail before keeping the new copy.
Change Bitrate of MP3 Online
Need a particular MP3 bitrate? Choose 128, 192, 256 or 320 kbps for one recording or a batch. Create a new MP3, preview it and download — free in your browser.
After adding your file, keep MP3 and Quality / Bitrate selected. A higher bitrate does not restore lost audio detail.
How to change MP3 bitrate in three steps
Add your MP3
Choose Single File to preview one recording, or Batch Compress for up to 10 files. Your original stays unchanged.
Choose your bitrate
Keep the output as MP3 and select Quality / Bitrate. Pick a preset or move the Bitrate slider to your desired setting.
Create and download
Click Compress Audio to encode the new MP3. Compare file sizes, preview in Single File mode, then download the result.
MP3 bitrate and file size, side by side
For the same recording length, more kilobits per second usually mean a larger file. Use the figures below to compare encoding settings, not to predict an exact download size.
| Bitrate | 1 minute | 5 minutes | What to expect |
|---|---|---|---|
| 64 kbpsA compact speech copy; check that words remain clear. | 0.48 MB | 2.40 MB | A compact speech copy; check that words remain clear. |
| 128 kbpsThe Balanced preset for comparing sound and size. | 0.96 MB | 4.80 MB | The Balanced preset for comparing sound and size. |
| 192 kbpsThe High Quality preset with more data per second. | 1.44 MB | 7.20 MB | The High Quality preset with more data per second. |
| 256 kbpsA higher-bitrate output when a delivery setting calls for it. | 1.92 MB | 9.60 MB | A higher-bitrate output when a delivery setting calls for it. |
| 320 kbpsThe highest MP3 setting available in this tool. | 2.40 MB | 12.00 MB | The highest MP3 setting available in this tool. |
Size estimate = bitrate × duration ÷ 8. These settings change the encoded data rate, not the length or playback speed of your recording.
Lower the bitrate, match a requirement, or standardize a batch
Choose a required kbps value
If a destination asks for 192 kbps, select 192 in Quality / Bitrate. Do not use Target Size for this job: that mode may lower the bitrate to fit its MB target.
Use one setting for several files
Apply the same MP3 bitrate to a batch of recordings. Files are encoded one at a time and can be downloaded separately or together as a ZIP.
Need a file under a specific MB limit instead? Use MP3 Compressor with Target Size. For other source and output formats, visit Audio Compressor.
Check more than the bitrate number
A higher number is not a quality repair
A 128 kbps source exported at 320 kbps is still based on the same limited source. Use a higher-quality original when available. Otherwise keep the original alongside the new file.
Read the full delivery specification
This tool exports MP3 at 44.1 kHz and uses two channels at 64 kbps or above. It has no separate sample-rate, channel or CBR/VBR controls. Check those requirements before submitting a file.
Review sound and file information
Listen in Single File mode, then check the downloaded MP3 in your destination or an audio file inspector. An MP3 encoder can round unsupported intermediate slider values; use common settings such as 128, 192, 256 or 320 kbps.
MP3 bitrate changer FAQs
How do I change the bitrate of an MP3 file?
Add your MP3, keep MP3 selected as the output format, and choose Quality / Bitrate. Select a preset or adjust the Bitrate slider, then click Compress Audio. Listen to the result in Single File mode and download a new MP3. Your original file stays unchanged.
Can I convert a 320 kbps MP3 to 128 kbps?
Yes. Keep MP3 as the output format and choose the Balanced preset at 128 kbps. For the same duration, its audio data uses roughly 40% of the space of a 320 kbps file, before overhead. Listen to the result because re-encoding is lossy.
Does converting 128 kbps to 320 kbps improve the sound?
No. You can choose 320 kbps for the output, but it cannot recreate detail missing from a lower-bitrate source. It generally produces a larger file. If you have the original WAV or FLAC, use that source to make a new MP3 instead of repeatedly re-encoding an MP3.
Which MP3 bitrates can I choose?
The MP3 control spans 32–320 kbps. Presets include 64, 96, 128 and 192 kbps; use the slider for settings such as 256 or 320 kbps. MP3 encoders use supported bitrate steps, so an in-between slider value may be rounded. Below 64 kbps, this tool exports mono audio.
Can I change the bitrate of multiple MP3 files together?
Yes. Choose Batch Compress and add up to 10 files, with a 100 MB limit per file and a 300 MB total batch limit. Select MP3 and Quality / Bitrate to apply the same encoding setting to the batch. Download completed files individually or in a ZIP.
Is bitrate the same as sample rate or volume?
No. Bitrate, measured in kbps, describes the amount of encoded audio data per second. Sample rate measures samples per second in Hz, and volume describes the playback level. This tool changes encoding settings; it does not boost volume or change playback speed.
View all 9 questionsShow fewer questions
Can I choose MP3 sample rate, channels or a VBR mode?
Not separately in this tool. MP3 export uses 44.1 kHz and two channels at 64 kbps or above; below 64 kbps it uses mono. There is no CBR/VBR switch. If a delivery specification also requires particular channels or a different sample rate, choosing the bitrate alone does not meet the whole specification.
Will my MP3 tags and cover art be kept?
Do not rely on this tool to preserve them. The compressor creates a new audio-only file and removes source metadata during encoding. Keep your original, and use the MP3 Tag Editor if you need to add titles, artists or cover art to the output.
Is the MP3 bitrate changer free and private?
Yes. Processing runs locally in your browser without an account. Your audio is not uploaded for encoding. The processing engine must load on the first run, and large files depend on your device memory. Keep the tab open until the new MP3 is ready.
Need to change the sound rather than its encoding? Edit audio or increase audio volume. To edit titles and cover art, use MP3 Tag Editor.