Bleep Censor Tool
Bleep out words in a podcast, interview, school project or video. Drag across each word on the waveform, press M while it plays, or let the tool find the words in your subtitles; then replace them with a classic beep, silence or a quiet duck and download the result. Everything runs on your own device.
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Drag across a word to mark it · drag a region's edges to adjust · click to move the playhead · M marks at the playhead · Del deletes the selected region
Censor style
Censored regions
Auto-mark words from a transcript (SRT, VTT, timed lines or Whisper JSON)
Timestamps from subtitles are per line, so word positions inside a line are estimated from their place in the text. Check each mark and drag its edges if needed. Whisper JSON with word timings is exact.
How to use the Bleep Censor Tool
- Open your audio or video file. A demo voice with two marked words is loaded so you can hear how it works.
- Mark the words: drag across each one on the waveform, press M while it plays, or paste subtitles under Auto-mark words and press Find words and mark them.
- Choose the censor style: Beep, Silence or Duck. Adjust the beep pitch, level and padding if you like.
- Preview with Play, switching between Censored and Original. Drag region edges or type exact times to fine-tune.
- Download the censored WAV, or press Export censored video to get the video back with the new sound.
Choosing a censor style
| Style | What you hear | Best for | Typical settings |
|---|---|---|---|
| Beep | A steady tone over the word | Comedy clips, reaction videos, TV-style edits | 1,000 Hz at -12 dB, 30 ms padding |
| Silence | A short gap | Podcasts, interviews, classroom recordings | 20 to 40 ms padding, 8 to 15 ms fade |
| Duck | The word becomes a quiet mumble while music continues | Videos with background music, vlogs | -20 to -30 dB, 15 ms fade |
Tips for accurate bleeps
- Zoom in (4× to 16×) to see each syllable as a separate bump on the waveform. A word usually starts at a sudden rise after a small dip.
- Use M while listening for a quick first pass, then fix the edges by dragging or typing exact times.
- Cover the whole word. Hard consonants at the end (t, k, ck) are short but recognisable; the padding setting adds a safety margin on both sides.
- Get word timings from a speech-to-text tool that exports Whisper-style JSON with per-word start and end times; then marks are exact instead of estimated.
- Keep the bleep a little quieter than the voice. A tone at full volume is harsh; -12 to -18 dB sits at a similar loudness to normal speech.
Supported transcript formats
| Format | Example | Word timing |
|---|---|---|
| SRT subtitles | 00:00:01,200 --> 00:00:03,900 | Estimated within each line |
| WebVTT subtitles | 00:01.200 --> 00:03.900 | Estimated within each line |
| Timed lines | 0:12.5 Oh heck, not again | Estimated until the next line |
| Whisper JSON | {"word": " heck", "start": 4.1, "end": 4.4} | Exact |
Frequently asked questions
How do I bleep out a word in a video?
Open the video, play it and press M as soon as you hear the word (or drag across it on the waveform), check the result with Play, then press Export censored video. The picture is copied unchanged and only the soundtrack is replaced, so the export is quick and the image quality does not change.
What frequency is the classic TV bleep?
Broadcast bleeps are usually a pure sine tone of about 1,000 Hz, which is the default here. You can set anything from 100 to 8,000 Hz; lower tones around 500 to 800 Hz sound softer, while higher ones are more noticeable. The beep level is set in decibels below full scale, -12 dB by default.
Can it find the words automatically?
Yes, if you have a transcript with timestamps. Paste or open SRT or VTT subtitles, lines like 0:12.5 text, or Whisper JSON, list the words to censor and press Find words and mark them. Subtitle timestamps cover whole lines, so word positions inside a line are estimated from where the word sits in the text; Whisper JSON with word timings is exact. Always listen to each mark and adjust if needed.
What is the difference between beep, silence and duck?
Beep replaces the word with a tone, the familiar TV style. Silence removes the sound completely, which is less distracting in podcasts. Duck lowers the volume (by 24 dB by default) so the word becomes unintelligible but the background music or room sound continues naturally.
Why add padding and fades?
Words often start and end a little before or after where they look on the waveform, so 20 to 50 ms of padding makes sure no syllable slips through. Short fades of a few milliseconds at the region edges prevent clicks where the sound switches to the beep.
Which file comes out?
Audio is saved as a 16-bit WAV, which every editor and player accepts. Video is saved in the same container as the input (MP4, MOV, WebM or MKV) with AAC audio, or Opus for WebM; it uses FFmpeg compiled to WebAssembly, which downloads once (about 31 MB).
Is my recording uploaded?
No. The sound is decoded, edited and saved with your browser's Web Audio API on your own device, and the optional video export also runs locally.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.