Reverse voice recorder

This page is the record-then-reverse path: one tab, a microphone, a reverse preview, a WAV download. You do not need Voice Memos or a desktop DAW for a take that fits in a minute. The capture uses the browser’s getUserMedia API. The reverse uses Web Audio on the same AudioBuffer. Both stay local. There is no speech-to-text, no pitch shift, and no paste-a-URL box.

If you already have a file, skip Record and use Upload. The recorder exists for people who want to hear their own sentence backwards without exporting from another app first.

Microphone permission

Chrome, Edge, Firefox, and Safari all ask before the mic opens. The prompt names this origin. Allow once if you trust the page; block if you do not. A blocked mic cannot be overridden by the Record button. You must change the site setting:

• Chrome / Edge: lock icon in the address bar → Microphone → Allow, then reload.
• Safari on Mac: Safari → Settings → Websites → Microphone.
• Safari on iPhone: Settings → Safari → Microphone, or the site settings panel from the “aA” menu depending on iOS version.
• Firefox: permissions in the address bar, then reload.

HTTP pages cannot use the mic on modern browsers; the site must be HTTPS. If you are on a private network with a self-signed cert, the prompt may never appear.

Permission is per origin, not per file. Granting it does not send audio anywhere. It only unlocks the device.

Hardware notes and an alternate framing of the same capture path sit on reverse audio microphone. A broader recorder article is reverse audio recorder.

The 60-second cap

The on-page timer stops the take at 60 seconds. That is a product limit, not a browser limit. It keeps memory predictable on phones and keeps accidental hour-long captures from freezing a tab.

Workarounds if you need more:

• Record in Voice Memos, a computer recorder, or a call-export tool, then upload. Uploads can exceed 60 seconds until RAM runs out.
• Record several 60-second takes, download each WAV, and concatenate in an editor. This page will not stitch them.

There is no pause. Stop writes the buffer. Record again replaces it. Download before you record over a take you want to keep.

Noise, gain, and what reverse does to a room

Phone mics run automatic gain. A quiet room still contains fridge hum, HVAC, and computer fans. Forward playback hides some of that under speech. Reverse playback puts the noise envelope backwards, so a decaying hiss becomes a rising hiss and sits on top of consonants.

Practical capture:

• Hold the phone 15–20 cm from your mouth.
• Turn off speaker playback while recording; the mic will reverse that bleed into a howl.
• Mute notifications. A lock-screen chime in the middle of the take becomes a reversed chime at an unpredictable time.
• Prefer headphones for monitoring after the take, not during, unless you are using a headset mic.

If the reversed result is still noisy, the source is the room, not the reverse algorithm. Re-record. Do not expect a denoise button here; there is none.

Speech-focused listening notes without the recorder emphasis are on voice reverser.

After you hit Stop

The buffer is reversed for preview by default on this workflow. Toggle Normal if you need to check that you said the right words. Speed 0.5x–2x is preview only; the download remains the reversed buffer at the capture sample rate (often 48 kHz from a phone, 44.1 kHz from some desktops).

Download WAV to keep the take. If you close the tab first, the recording is gone. The file is WAV even if you thought you were making an M4A memo. Chat apps that reject WAV need a conversion after download.

To send a reversed joke, download and attach. To restore later, upload that WAV and reverse again.

Phone versus desktop capture

On a laptop, the built-in mic is farther from the mouth and more roomy. A USB headset is cleaner. On a phone, use the bottom mic unless you know your model’s primary capsule. Small-screen layout, memory, and headphone routing are collected on reverse audio on mobile.

Backgrounding the browser on Android can cut the mic. Stay in the tab until Stop. iOS Safari may also suspend audio if you switch apps mid-take; finish the 60 seconds in the foreground.

Bluetooth headsets add latency and sometimes a narrow voice band. Reverse does not restore missing highs. Wired or built-in mics give a fuller buffer.

Upload instead of record

Voice Memos, Android recorders, and chat exports belong in the file picker. iPhone memos are usually M4A; see reverse voice memo. WhatsApp notes are often OGG. The decoder accepts MP3, WAV, FLAC, OGG, M4A, and AAC. It does not fetch a Drive or iCloud URL.

If Record is blocked at work (policy, missing HTTPS, no mic hardware), upload is the remaining path.

What you will not find on this recorder

• Pitch or formant sliders.
• A translation or caption.
• Multi-track punch-in.
• Cloud backup of takes.
• Batch capture of several mics.

The product is a single mono or stereo buffer reversed in time. Stereo depends on the device; many phones deliver mono. Channels that exist are reversed independently, left staying left.

Keep the original spoken intent in mind: a reversed recorder is for backwards playback and WAV export, not for replacing a hardware field recorder.