Blend Audio Tracks Online

Blending audio tracks lets you layer music and voice, add background sound, build mixes, and create richer audio. Where a merger plays your files one after another, a blender plays them at the same time — so a voiceover sits on top of a music bed rather than after it.

Benefits of audio blending

• Mix audio: Combine tracks with independent volume control on each one.
• Layering: Create a fuller sound by stacking sources that play together.
• Timing control: Trim each track and delay any of them so they line up.
• Polish: Use fades, pan, presets, ducking, loudness targets and a limiter.
• Export options: Download as MP3, WAV, M4A, AAC, OGG or FLAC.

This tool sums two or more tracks into one, with adjustable volume, per-track trim, delay and pan, optional automatic ducking, fades on the finished mix, and optional loudness normalization. You can hear the mix before you commit to it and export when it sounds right.

Features (in depth)

• Waveform timeline: See every track's waveform in position, with delays applied, and scrub to any point.
• Live preview: Play and stop the mix in real time with a peak meter and a clipping indicator.
• Trim per track: Set a start and end for each track to cut silence or unwanted parts.
• Volume and pan: Set each level from 0% to 200% and place each track anywhere from hard left to hard right.
• Delay: Start any track later than the others, to the millisecond.
• Automatic ducking: Pick the track that leads, and every other track drops out of its way while it plays.
• Fades: Fade the finished mix in and out, bounded so the two can never overlap.
• Loudness: Level the mix dynamically, or hit an exact LUFS target for Spotify, podcast or broadcast delivery.
• Limiter: Hold the true peak under the ceiling so the export cannot clip.
• Presets: Voice over music, podcast mix, ambient blend, karaoke and equal mix.
• Blend length: Stop when the shortest track ends, or run to the longest.
• Export: MP3, WAV, M4A, AAC, OGG and FLAC, with bitrate and sample-rate choices where they apply.

Blending process

• Add tracks: Select two or more audio files. They are read on your device and never uploaded.
• Set the mix: Adjust volume, pan, trim, delay, ducking, fades and loudness.
• Preview: Use the waveform and live playback to verify the timing and the balance.
• Blend: Choose output settings and run the blend.
• Download: Save the blended file straight to your device.

Ducking is the effect you hear on every radio advert and every podcast intro: the music drops out of the way the moment somebody speaks, then swells back in the gaps. Doing it by hand means drawing a volume curve around every sentence. Here you pick which track leads and the tool follows it.

How it works

• You nominate one track as the key — usually the voice.
• Whenever the key track rises above the threshold, every other track is pulled down.
• The amount it drops is set by the ratio; how quickly it drops and recovers is set by attack and release.
• In the gaps between phrases the other tracks return to their own level, untouched.

What the settings actually do

• At the default ratio of 8, a music bed under a voice measures 19 dB quieter while the voice is present, and returns to exactly its own level in the gaps.
• Raising the ratio deepens the duck: 2 gives about 11 dB, 4 about 17 dB, 20 about 21 dB.
• A ratio of 1 is no ducking at all, which makes it a useful way to hear the difference.
• A slower release keeps the music down between short phrases instead of pumping up and down between words.

A mix that sounds right on your headphones can still be rejected by a platform, because streaming services measure loudness rather than peak level. This tool can measure the finished blend and move it onto an exact target.

The two loudness options

• Level out (dynamic): Evens out a track whose loudness wanders, without aiming at any particular number. Good when one source was recorded much hotter than the other.
• Hit a target (LUFS): Measures the whole mix, then applies one gain so the integrated loudness lands on the target exactly. Spotify is −14 LUFS, podcast delivery is −16, broadcast is −23.

Peak is not loudness

• Peak level is the single loudest sample; loudness is how loud the whole thing seems over time. Two files can share a peak and be worlds apart in loudness.
• A loudness target implies a peak ceiling as well, so the limiter is applied automatically whenever a target is set.
• Normalizing to a target can make a quiet mix louder or a hot one quieter — it moves the level onto the number, in whichever direction that is.

Every format here is written on your device. The right one depends on what happens to the file next.

• MP3: Plays everywhere. The safe choice for sharing, uploading or attaching.
• M4A and AAC: Better quality than MP3 at the same bitrate. M4A is the MP4 container; AAC is the raw stream.
• OGG: Free and open, well supported on the web and on Android.
• WAV: Uncompressed. The right choice if the mix is going into another editor afterwards.
• FLAC: Lossless but compressed — WAV quality at roughly half the size.

A few practical points that make the difference between a mix and a mess.

Key points

• Good volume balance matters far more to a clean mix than which file format you pick.
• Trimming silence and lining the tracks up usually does more for clarity than any effect.
• Ducking beats simply turning the music down, because speech is not at a constant level.
• Export format affects file size: WAV and FLAC are larger than MP3, M4A, AAC and OGG.
• Very long or very high-sample-rate audio takes longer to process, because everything happens on your device.

Tips for smoother results and fewer surprises.

Quality considerations

• Start from a preset, then fine-tune the volumes rather than starting from scratch.
• Watch the peak meter. If the clipping light comes on, lower a level or switch the limiter on.
• Trim the intro and outro and add a short fade, so the mix does not start or end with a click.
• If you are exporting to MP3, M4A, AAC or OGG, avoid re-encoding the same audio repeatedly.
• Use WAV or FLAC when the mix is going on to another editing step, and a compressed format for sharing.
• Set a LUFS target if the mix is going to a streaming platform, so it is not turned down on arrival.

Common use cases

• Voice over music: Keep the speech clear and let the music duck automatically underneath it.
• Podcast mix: Add a bed of ambience, duck it under the hosts, and normalize to −16 LUFS.
• Karaoke: Blend a backing track with a recorded vocal and balance the two.
• Sound design: Layer effects and atmospheres, each panned to its own place.
• Creator workflows: Drop a voice track onto a beat and have a shareable file in seconds.
• Audio description: Sit a narration track above a programme mix without burying it.

Everything on this page happens on your own device. Your tracks are read from disk, mixed and written back out without a single byte being sent anywhere.

• No upload, so nothing is queued on a server and nothing is stored after you close the tab.
• Nothing to install — the tool works the moment the page has loaded.
• The mix runs at the speed of your own hardware, which is why a longer file takes longer.
• Because the processing is local, the tool keeps working if your connection drops mid-mix.

Powered by an on-device audio engine — nothing is uploaded.

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