BYTETOOLS

Audio Sample Rate Converter

Convert audio sample rate online for free. Resample to 8, 16, 44.1 or 48 kHz for video, speech tools or telephony — right in your browser, nothing uploaded.

Drop an audio file here or click to browseYour audio is resampled locally and never uploaded.

What is the Audio Sample Rate Converter?

The ByteTools Audio Sample Rate Converter resamples audio to a new rate — 8 kHz for telephony systems, 16 kHz for speech-recognition engines, 44.

  • Presets: 8 kHz telephony, 16 kHz speech, 44.1 kHz CD, 48 kHz video
  • Optional mono/stereo channel conversion in the same pass
  • High-quality swresample resampling engine
  • WAV (PCM) or MP3 output
  • 100% local — audio is never uploaded
  • Free, unlimited and works offline once loaded

How to use the Audio Sample Rate Converter

  1. 1

    Drop an audio file onto the box or click to browse for one.

  2. 2

    Choose the target sample rate — presets cover telephony, speech, CD and video.

  3. 3

    Optionally set the channel count and pick WAV or MP3 output.

  4. 4

    Click Convert Sample Rate and preview the result.

  5. 5

    Download the resampled file.

About the Audio Sample Rate Converter

The ByteTools Audio Sample Rate Converter resamples audio to a new rate — 8 kHz for telephony systems, 16 kHz for speech-recognition engines, 44.1 kHz for CD audio and music, or 48 kHz for video work. It can also downmix to mono or force stereo in the same pass, then outputs WAV or MP3.

Sample-rate requirements come up constantly: transcription APIs that expect 16 kHz mono WAV, video editors that want 48 kHz, IVR and PBX systems built around 8 kHz, and mastering workflows targeting 44.1 kHz. This tool uses ffmpeg's swresample engine, the same high-quality resampler used across the industry.

Everything runs 100% locally in your browser using WebAssembly. Your audio is never uploaded to any server — no accounts, no limits — and the tool keeps working offline once the engine has loaded.

Frequently asked questions

What sample rate should I use for speech recognition?

Most speech-to-text engines are trained on 16 kHz mono audio, and several APIs require it outright. Choose 16 kHz, set channels to mono and output WAV — that combination satisfies virtually every transcription service.

Does changing the sample rate affect audio quality?

Downsampling removes all frequencies above half the new rate (the Nyquist limit) — at 8 kHz everything above 4 kHz is gone, which is fine for voice but bad for music. Upsampling never adds quality; it only makes the file compatible with a target that demands the higher rate.

What is the difference between 44.1 kHz and 48 kHz?

44.1 kHz is the CD and music standard; 48 kHz is the video and broadcast standard. Both capture the full audible range. Match whatever your destination uses to avoid an extra resample later — video editors almost always want 48 kHz.

Why does my file need to be 8 kHz?

Telephony systems — IVR menus, PBX hold music, SIP platforms — descend from 8 kHz digital telephone standards and many still require 8 kHz mono WAV files. This tool produces exactly that.

Is my audio uploaded to a server?

No. Resampling runs entirely in your browser using WebAssembly, so your file is processed on your own device and never sent anywhere.

Related tools