Record or load audio and edit the needed sections
Adjust start/end, silence, playback speed, and save format while viewing the waveform.
Provide audio
Microphone recording starts only when you press the button. Files are not uploaded.
Please record audio or select an audio file.
Waveform and edit range
Silence, speed, and save
Provide audio and adjust the threshold.
Recordings and audio files are not sent externally.
What you can do with the Audio Recording, Trimming, and Silence Removal Tool
Record audio in your browser or load an existing audio file, then trim the sections you need while viewing the waveform. Automatically detect silence at the start, end, or long pauses in the middle, and save the edited audio as 16-bit PCM WAV.
You can choose the preview playback speed, mono or stereo, and 44.1kHz or 48kHz. Recordings, audio files, and edited results are processed in the browser and are not sent to transcription APIs or external servers.
Record and load files
Microphone recording starts with an explicit action, and loads formats the browser can play, such as MP3, WAV, M4A, and WebM.
Check range on waveform
The selected range and detected speech sections are color-coded, and start/end can be adjusted in 0.01-second increments.
Two types of silence removal
You can choose to trim only the ends or to remove silences of a certain duration in the middle.
Save reliably as WAV
Creates an uncompressed WAV on your device, which is less dependent on the browser’s encoder support.
Steps to record audio and cut out unwanted parts
- Start microphone recordingAllow the microphone used in the browser’s permission check. Check the recording status.
- Stop recordingWhen you stop, the recording data is loaded and the waveform and length are displayed.
- Adjust start and endSpecify the range to keep using the number fields or the slider.
- Detect silenceCheck the detection results; if more than needed is being removed, lower the threshold.
- Play and save the selected rangeMake sure the beginning and end of words are not cut off, then save as WAV.
How to adjust silence removal threshold
| Settings | Effects | Note |
|---|---|---|
| -55〜-50dB | Small ambient sounds are easy to keep as audio | Silence may hardly be removed in some cases |
| Around -45 dB | Starting value for quiet indoor conversation | Listening is needed to match your microphone and room |
| -35〜-25dB | Tends to keep only loud sounds | High risk of cutting quiet speech or word endings |
| Minimum length | Keep short breaths, remove long pauses | Cutting mid-sentence changes the rhythm of the speech |
| Leading/trailing margin | Keep a little before and after speech | Setting to zero may cut consonants |
Automatic detection does not understand the content of the audio. Before saving, listen to the whole thing and check that proper nouns, quiet speech, the other party on the phone, and sound effects are not missing.
Difference between playback speed and saved audio
The “Preview playback speed” only makes the playback during checking faster or slower and does not normally affect the saved audio. If you select “Apply speed to the saved WAV as well,” the audio samples are simply compressed or stretched, so the pitch changes along with the speed.
High-quality time-stretching that preserves pitch, noise removal, equalizer, and volume normalization are not included. For important recordings, use dedicated editing software while keeping the original data.
WAV format and size for saving
The output format is uncompressed 16-bit PCM WAV. At 44.1 kHz, mono is about 5 MB per minute, and stereo is about 10 MB per minute. At 48 kHz, it is slightly larger. For long recordings, check your browser’s memory and available storage space.
Compressed saving to MP3 or AAC is not done because browser built-in features vary greatly by environment. The original WebM recording, for example, can be saved separately only if it is the original format created by the browser’s MediaRecorder.
Microphone permission and recording issues
Recording works on HTTPS pages or local environments with a supported browser. If you denied permission, check the site settings near the address bar and your OS privacy settings. On company-managed PCs, administrator policies may prevent use.
Even when a Bluetooth device is connected, a different microphone may be selected. Check the input device and level on the OS side, and save and play a short test before important recordings.
Processing without uploading audio
Recording, decoding, waveform display, trimming, silence detection, playback, and WAV creation all happen in your browser. Audio is not sent to WiseChecker’s servers, external APIs, or generative AI. Click “Clear Audio” or reload the page to discard the audio reference and temporary URL on screen.
FAQ for audio recording and editing
Will it automatically transcribe after recording?
It does not. Since the policy is not to send to external APIs, a transcription feature is not included.
Can I save as MP3?
After editing, it is saved as WAV. This is to avoid differences in MP3 encoding between browsers.
Can I remove all silences in the middle?
There is a setting to remove silences longer than a certain duration. Since the meaning and rhythm of the conversation may change, listen before saving.
Cannot load M4A
Supported codecs depend on the browser and OS. Try a copy converted to WAV or MP3.
Is audio sent to a server?
Nothing is sent. Processing happens on your device.
Does editing also change the original file?
It does not change. The edited result is saved as a new WAV.