FREE TOOLS
Free audio tools,and your files never leave your device.
12 handy audio tools — convert, edit, change pitch, adjust volume, remove noise, record — all in your browser. No uploads, and free up to 200MB a day once you log in.
- No uploads
- Log in to use
- 200MB free per day
- ¥0.2 per run after that
Format
Change formats, get audio from video, work with stereo channels
Video to Audio
Save the sound from short videos, performance recordings and class recordings as audio files.MP4 · MOV → MP3 · WAV · FLAC · M4AOpenAudio Format Converter
Won't play on your phone, or your software won't open it? Convert between MP3, WAV, FLAC and M4A.MP3 · WAV · FLAC · M4AOpenStereo Channel Tool
Extract the left or right channel, swap them, or convert to mono; spots KTV files with separate left and right channels.Left · Right · Swap · MonoOpen
Edit
Cut, join, make phone ringtones
Audio Cutter
Drag on the waveform to clip a chorus, make a ringtone, or trim the silence at the start.Drag to select · Fade in/outOpenAudio Joiner
Join recordings or songs into one file in order, with crossfades or gaps at the joins.2–20 files · Crossfade · GapOpenRingtone Maker
Pick your phone and clip the chorus: M4R for iPhone, MP3 for Android, with setup steps.iPhone M4R · Android MP3Open
Tune
Change pitch and speed, find key and tempo
Quality
Adjust volume and tone, remove background noise
Volume Adjuster
Turn audio up or down, or normalize to common loudness levels like −14, −16 or −23 LUFS; with clipping protection on, peaks stay under −1 dBTP.±20 dB · Loudness matching · Clip protectionOpenOnline Equalizer
Clearer vocals, more bass, less low-end hum, or tune 5 bands yourself while comparing with the original.MP3 · WAV · FLAC · M4AOpenVoice Denoiser
Remove air-conditioner noise, electrical hum and background noise from voiceovers, recordings and a cappella vocals; not for songs with music.Light / Medium / Strong · Before & afterOpen
Record
Record right from the web page
§ 01Uses
What do you want to do?
- Save a song or dialogue from a video as audioVideo to Audio
- Phone or car stereo won't play FLAC or WAVAudio Format Converter
- Editing software only accepts WAVAudio Format Converter
- KTV dual-channel song — keep just the backing sideStereo Channel Tool
- Need just one part of a long recordingAudio Cutter
- Join several recordings into one fileAudio Joiner
- Cut a song into a 30-second ringtoneRingtone Maker
- Change the key, or slow a song down to practicePitch & Tempo
- What key is this song in, and what BPM?Key & BPM Finder
- Backing track too quiet, or songs jumping in volumeVolume Adjuster
- Sound is muffled, not enough bassOnline Equalizer
- Background noise in a voiceover or recordingVoice Denoiser
- Record yourself singing over a backing trackOnline Recorder
- Remove the vocals, keep the backing trackBacking-track separationPaid · Preview first
§ 02How it works
Why don't files need uploading?
Decoded in your browser
The processing code loaded with the page reads your file and decodes the sound right in your browser — no server involved.
Re-encoded on your device
Encoders for MP3, FLAC and other formats also run on your device, so speed depends on your hardware.
Cleared when you close the page
Results live only in this page's memory, and you save them when you download; close or refresh the page and they're gone.
§ 03FAQ
Q1Does it cost anything?
Processing is free up to 200MB a day, counted by file size and reset at midnight Beijing time. After that, each run costs ¥0.2, taken from your wallet balance rather than your songs, and you'll be asked before anything is charged; if a run fails or you cancel it, the charge is refunded (up to 5 times a day). Plus members and above get unlimited use while their membership is active. Backing-track separation is a separate paid feature, and whether to use it after processing is up to you.
Q2Will my files be uploaded?
No. Processing happens entirely in your browser, and your files never pass through our servers. They're uploaded only if you click "Make a backing track" on the result page and confirm on the next page.
Q3Does it work on phones?
Yes — just open it in your phone's browser. In WeChat you can process and preview too, but WeChat can't save files, so tap "···" in the top-right corner, open it in your browser, and log in there.
Q4Is there a file size limit?
Videos up to 2 GB, audio up to 500 MB. Compatibility mode (some WeChat in-app browsers) handles up to 300 MB and 30 minutes.
Q5How long can audio be for tools like pitch change or denoising?
Tools that load the whole audio into memory first (joiner, pitch, key detection, volume, EQ, denoiser, channels) handle up to 20 minutes at a time; denoising needs more processing power, so go by the limit shown on its page. Video to audio, format conversion and cutting process as they read, so this limit doesn't apply. Phones have less memory, so we suggest one file at a time.
§ 04Backing-track separation
Done processing — want the vocals gone?
Click "Make a backing track" on any tool's result page — no need to find the file again. Preview 25 seconds for free first, and pay ¥4.9/song only if you're happy.