How to Mix Multiple Audio Tracks into a Video or Merge Audio Files Online

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How to Mix Multiple Audio Tracks into a Video or Merge Audio Files Online

Last Updated: 2023. 05. 06

The importance of audio mixing in video editing can’t be overstated. Audio files like ambient sound, dialogues, background music, and sound effects all need to be well-mixed to enhance the auditory experience for the viewers.

In this post, we’ve rounded up 3 handy audio mixers online for you and will walk you through their different features to combine audio files. So, you can easily mix two or multiple audios into a video in minutes or merge multiple audio files into an MP3 or WAV, etc.

Here’s What You Will Learn:

How to Mix Multiple Audio Tracks into a Video by FlexClip

2 Other Free Audio Mixers Online to Combine Audio Files

Also, read how to transcribe podcasts to text.

How to Mix Multiple Audio Tracks into a Video by FlexClip

If you are working on your podcast video, YouTube video, or movie intro and need to mix audio files like background music, sound effects, and voiceovers into the video, then the feature-packed FlexClip online video maker is exactly what you need.

Easily mix audio files using FlexClip online audio mixer and video editor.

Mix Audio Now

With FlexClip, you can seamlessly mix audio files on an intuitive and magnetic timeline and use vast royalty-free audio assets, with no experience and no plugin download needed.

Best Features for Mixing Audio and Video:

Easily layer multiple audio files on different audio tracks to do J Cut and L Cut or complex audio layering to create dimension and depth to your video projects.

Extract audio from imported videos and trim and split extracted audio to select portions of the audio, such as music, dialogue, and sound effects for audio mixing.

Extract audio from videos for audio mixing.

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Trim, split, mute, and duplicate audio files and adjust their volume in a breeze.

Add fade in/out effect to smooth out the audio transition.

Apart from mixing your audio files, you can make the most of 74,000+ royalty-free music tracks and sound effects within FlexClip.

Besides, FlexClip also offers you thousands of fully-customizable video templates, covering lyric videos, podcasts, YouTube videos, webinars, movie trailers, holidays, slideshows, promo videos, travel, etc. Just by easy drag and drop, you can create a compelling video in minutes.

Preview

Purple Lyrics Template

Use This Template

Preview

Youtube Music Podcast Intro Outro

Use This Template

Preview

Tech Movie Trailers Technology

Use This Template

Preview

Travel Memories Slideshow Youtube Video

Use This Template

What’s more, you may also use a free text-to-speech generator to create realistic ai voices and get them mixed with royalty-free music and sound effects for your video project and use the auto subtitle generator to auto-generate subtitles with one click and up to 95% accuracy and you can easily customize the style of subtitles.

Create realistic AI voices for audio mixing.

Use Free TTS

Automatically add subtitles to your videos.

How to Mix Audio Online by FlexClip:

Step 1

Access FlexClip and upload your audio files and footage from your PC, phone, Google Drive, One Drive, Dropbox, or Google Photos.

Upload your audio and video assets to FlexClip.

Step 2

Click the plus sign to add audio files and footage to the timeline. If you need to trim or split the footage, you may use the trimmer and split tool to do the rough cut when needed.

Add audio files and footage to the timeline.

Alternatively, you can import a video > right-click on it > select detach audio to extract audio from the video. So, you can trim or split audio to use portions of music, dialogues or sound effects for audio mixing. Pretty handy!

Extract audio from imported video and use portions of audio for audio mixing.

Extract Audio Now

Step 3

Do the audio mixing.

As you hover over an audio file, its name will show up automatically. You can drag and hold to adjust its sequence on the timeline or drag one end of an audio file to extend it to another footage to create the classic J Cut or L Cut effect.

Use J Cut and L Cut to mix audio tracks.

Or you can trim or split unwanted background noise, filler words, and silence in the audio narration.

Split, trim, and delete audio files with filler words and silence.

To avoid abrupt arrival or end of background music or sound effects, you can add fade in/out effects to make it sound more natural. Or lower the volume of the ambient sound so as not to disturb the audio narration in the video.

Add fade in/out effects to the audio or lower its volume.

Bonus: Use royalty-free music and sound effects in FlexClip.

If you don’t have BGM or sound effects for your video project, no worries! Click the Audio tab and you can search for 74,000+ royalty-free and studio-like music tracks and sound effects available in FlexClip, which will help you create the vibes and rhythm for your video.

Use royalty-free music and sound effects to mix audio for your video projects.

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If the mixed audio has dialogues or lyrics, you can click the Subtitle tab > Auto AI Subtitle > identify the language in the audio tracks > hit Next > set the style of subtitles > hit the Generate Subtitle button.

Automatically add subtitles to your video with the click of a button.

Later, you can proofread the auto-generated subtitles and adjust the text font, text size, color, background fill, alignment, etc. Or press “Enter” to split long subtitles or merge short subtitles with ease.

Customize the style of auto-generated subtitles.

Easily split or merge subtitles.

Step 4

Preview and share.

Done with the editing. You can download the video to your hard drive or directly share it to YouTube, Google Drive, One Drive, Dropbox, or TikTok; a clickable link and an embed code are also available for your blog, newsletter, or other repurposing.

Share your video project in multiple ways.

Who is FlexClip Best-suited For?

For Vloggers, YouTubers, video podcasters, etc, FlexClip can offer you a hassle-free experience to mix audio tracks into a video in minutes. The vast royalty-free stock assets and powerful AI video, audio and image tools will be a huge bonus for your audio and video mixing.

2 Other Free Audio Mixers Online to Combine Audio Files

If all you need is to mix audio tracks online like combing a piece of music with your vocal and keep it as a merged audio file for the audio podcast or music production, then the 2 following online free audio mixers should serve you well.

1. Online Converter

Online Converter is a free audio mixer online that is capable of mixing up to 4 audio tracks into one in your browser and without any registration. Some of the audio formats it supports are MP3, WAV, OGG, M4A, and WMA. The only downside is that you can’t preview your new audio in real-time and features are so limited.

Mix multiple audio tracks by Online Converter audio mixer

Best Features for Mixing Multiple Audio:

Support up to 10 audio formats for audio mixing: MP3, OGG, MIDI, M4A, WMA, AMR, FLAC, ALAC, AIFF, WAV, and more

Set duration and transition for mixing audio

Easy share to Facebook, Twitter, Reddit, E-mail, Pinterest, Linkedin or your mobile phone

No registration required

Step 1

Upload Audio Files to Online Converter.

Step 2

Set the Duration and Transition of Mixed Audio File.

Step 3

Click the “Mix” Button to Combine Audio Files and Download or Share.

Who is Online Converter Best-suited For?

If you are satisfied with the original audio files and no more editing is needed, then you can use Online Converter to mix audio tracks in seconds.

2. Audio Joiner

Audio Joiner is a user-friendly audio mixer online made solely for audio mixing. Its minimal interface allows you to easily upload multiple audio files, then do the trimming and add fade in/out effect and combine all the audio files for download and share to Clouds.

Use Audio Joiner to mix multiple audio online for free

Best Features for Mix Multiple Audio:

Easy-to-use and minimal interface.

Support more than 300 audio formats.

Unlimited audio tracks for uploading and mixing. Awesome!

Trim each audio track, adjust audio position, add crossfade effect.

Mix audio files and Export as MP3, M4A, WAV, FLAC.

Local download, or share to Dropbox and Google Drive.

Step 1

Upload Audio Files to Audio Joiner.

Step 2

Edit the Audio Files.

You can trim audio files, add fade-in, crossfade effect, or drag audio sliders to set an interval between each audio.

Step 3

Select Audio Format for Download and Share.

Who is Audio Joiner Best-suited For?

With unlimited audio tracks for mixing and supporting more than 300 audio formats, Audio Joiner is a sweet and nifty online audio mixer for pure audio mixing. Vocalists, podcasters will love using Audio Joiner to mix audio for high-quality audio files.

Now, It's Your Move

To sum up, audio mixing in a video refers to balancing, editing, and combing all the audio files recorded for a video, and no audio mixer is made equal. Hopefully, you will find our recommended tools helpful. If you need to mix multiple audio tracks into a video, the versatility and huge royalty-free stock assets of FlexClip is the best choice. While the rest 2 audio joiners will meet your different needs. So, start combing audio files, now!

Mix Audio Now

Frank /

Passionate about photography, video-making and travel, Frank is a seasoned copywriter and a beloved father of 2-year-old daughter at FlexClip. He is always keen to share his latest discovery about video marketing and tricks to relive your memories through videos and images.