Video Voiceover Recorder
Narrate a screen recording, tutorial, gameplay clip or slideshow in sync with the picture. Play the video, talk into your microphone, redo any sentence by recording over it, balance your voice against the original sound with automatic ducking, and save the finished video, all inside your browser.
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Microphone
Recording over an existing take replaces that part only. R starts or stops recording, Space plays.
Mix
Choose a video and turn on your microphone to start.
How to use the Video Voiceover Recorder
- Choose your video. It opens locally; the original soundtrack is shown on the timeline.
- Turn on the microphone. Allow access when the browser asks and check the level meter moves when you speak. Wear headphones so the video sound is not recorded.
- Record. Move the playhead to where the narration starts and press Record (or R). After the count-in the video plays and your voice is recorded. Press Stop, R or Space to finish.
- Retake and mix. Record over any sentence you want to redo, delete takes you do not need, and set the original and voice volumes and the ducking amount. Press Play to hear the mix.
- Create the video. Click Create video with voiceover and download the result, or download the voiceover alone as WAV.
Recommended mix levels
The mix is calculated sample by sample: output = original × original volume × ducking gain + voice × voice volume. The ducking gain drops to the chosen dB level within about 80 ms of speech and recovers over about 350 ms after a 200 ms pause, so it does not pump between words.
| Video type | Original | Voice | Ducking |
|---|---|---|---|
| Tutorial or screen recording with background music | 40 to 60% | 100% | −15 dB |
| Gameplay commentary | 50 to 70% | 100 to 130% | −10 dB |
| Travel or event footage with natural sound | 70 to 100% | 100% | −8 to −12 dB |
| Silent slideshow or screen capture | 0% | 100% | Off |
| Reaction or commentary over speech | 60% | 110% | −18 dB or more |
Tips for a clean voiceover
- Write a short script or bullet points and read it once before recording. Short takes per sentence or paragraph are easier to redo than one long take.
- Keep a constant distance from the mic (about 10 to 20 cm). The level meter should peak in the green-to-orange area, never touching red.
- Leave a breath of silence before and after each sentence so a retake can start and stop cleanly.
- Soft furnishings, curtains and a closed door reduce echo far more than any filter.
- Speak a little slower than in conversation; narration over moving pictures needs time to be absorbed.
Frequently asked questions
How do I redo one sentence without re-recording everything?
Move the playhead just before the sentence and record again. The new take replaces only the time it covers; the rest of your earlier narration stays. You can also delete any take from the list under the timeline.
What is audio ducking?
Ducking automatically lowers the original video sound (music, game audio) while you are speaking and brings it back up in pauses. −10 to −15 dB is typical for narration over music; −20 dB or more makes the background almost silent under your voice.
Why should I use headphones?
If the video sound plays through speakers, the microphone records it again, slightly delayed, which sounds like an echo in the final mix. With headphones only your voice is captured. Alternatively, untick “Hear the video while recording”.
My voice is slightly late compared with the picture. How do I fix it?
Every computer adds a small recording delay. Raise the Latency correction slider (often 20 to 150 ms, Bluetooth headsets more) until the voice lines up; it moves all takes earlier at once and can be changed after recording.
Does exporting reduce the video quality?
No. With the default method, ffmpeg.wasm copies the video stream untouched and only encodes the new mixed audio (AAC for MP4/MOV, Opus for WebM). Only the real-time fallback re-encodes the picture.
Is my recording uploaded?
No. The microphone audio, the video and the mix are all processed in your browser and never leave your device. The ffmpeg engine (about 31 MB) is downloaded once when you first export.
What microphone settings are used?
The browser's echo cancellation, noise suppression and automatic gain control are turned on, which suits laptop and headset microphones. For the cleanest sound, record in a quiet room about a hand's width from the mic.
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.