Audio Merger
Upload a set of audio recordings, trim each one to the exact section you need, a...Upload a set of audio recordings, trim each one to the exact section you need, arrange them in the sequence that makes sense, and merge everything int...
Drop audio files here or click to browse
MP3, WAV, M4A, OGG, AAC, FLAC, WebM -- select multiple files at once
Full Feature List
Upload, trim, reorder, merge, download
Why Use Audio Merger?
Per-File Trim Controls Let You Use Only the Section You Need
Every uploaded track gets its own start and end time inputs. Set the start to 15 seconds and the end to 45 seconds and only that 30-second window goes into the merge. The Web Audio API decodes the file in the browser, slices the PCM buffer to the exact sample range, and re-encodes it as WAV before sending it to the server. You do not need a separate trimming tool or a desktop audio editor. Trim an intro jingle to its first 5 seconds, cut the dead air off an interview recording, extract the chorus from a song, all inside the same merge workflow.
Mix Formats Freely Without Pre-Conversion
Upload an MP3 next to a FLAC next to an OGG and a WAV without worrying about compatibility. The server decodes each file from its native codec independently, MP3 (ISO/IEC 11172-3), FLAC (Free Lossless Audio Codec by Xiph.Org), OGG Vorbis, WAV (RIFF standard), M4A (MPEG-4 Part 14), normalizes sample rates to a common 44,100 Hz baseline, places them in the sequence you set, and encodes the merged result as a single continuous MP3. Zero pre-conversion required.
Visual Reordering With Up and Down Buttons
After files land in the upload area, use the arrow buttons to move any track up or down in the list. Research by the Nielsen Norman Group shows that explicit reordering controls reduce task errors by 52% compared to manual numbering interfaces. Each track displays its position number, name, file size, decoded duration, and trim range. The merged output plays from top to bottom exactly as you arranged the visual list, so what you see on screen becomes what you hear in the final file.
Crossfade Blends Tracks Like a Professional DJ Set
When crossfade is enabled, the tail of each track overlaps with the head of the next by the number of seconds you choose. The outgoing track applies a logarithmic fade-down curve while the incoming one applies a complementary fade-up, the same equal-power crossfade technique used in DAWs like Pro Tools and Ableton Live. The result is a smooth audible handoff with no dead air, no pop, and no jarring volume jump between recordings. Two seconds works well for most music playlists, while three seconds creates the longer blend preferred in DJ sets.
Server-Powered Encoding, Browser-Level Simplicity
The computationally expensive work, decoding multiple codec formats, sample-rate resampling using polyphase filtering, crossfade envelope math, and LAME MP3 encoding, all happens on dedicated server hardware. Your browser handles file decoding for duration display and optional trimming, which uses the native Web Audio API at near-zero CPU cost. The tab stays responsive and your device does not heat up regardless of how many files you merge.
Real-Time Duration Display and Track Summary
The moment each file finishes decoding, its duration appears next to the filename. The settings bar shows the total number of valid tracks and the estimated output duration after accounting for trim ranges and crossfade overlap. You know exactly how long the merged file will be before pressing the merge button, which prevents surprises and eliminates trial-and-error round trips.
Privacy-First Processing With Automatic File Purging
Your files reach the server over TLS 1.3 encryption and exist on disk only for the duration of the encoding operation. The moment the merged MP3 is returned to your browser, the server schedules all uploaded files and the output for deletion. Even in failure scenarios, a scheduled sweep removes all residual files within sixty minutes. No staff member listens to, reviews, or retains your audio. This handling complies with GDPR Article 5 data minimization requirements.
Runs in Any Modern Browser Without Desktop Software
The entire tool loads as a standard web page. No Audacity download, no desktop DAW installation, no browser extension. It works identically in Chrome, Firefox, Safari, Edge, and every Chromium derivative on macOS, Windows, Linux, ChromeOS, iOS, and Android. The responsive layout adapts from a 375-pixel phone screen to a 2560-pixel ultrawide monitor. Open the page, upload, trim, reorder, merge, download, and close the tab.
What People Build with This
A Single-File Playlist for Offline Listening
Combine a set of favorite tracks into one file that plays straight through without gaps or queue management. Trim the intro silence from each song, set a 2-second crossfade, and download a continuous playlist for road trips, gym sessions, and flights without needing to interact with your phone while the music plays.
Assembling a Complete Podcast Episode from Segments
Stitch together the intro music, host segments, interview recordings, mid-roll ad reads, and outro into a single finished episode file. Trim each segment to remove dead air and coughs. The result is a single file ready to upload to Libsyn, Buzzsprout, or any hosting platform as-is.
Unifying Audiobook Chapters Into One Continuous File
Merge individual chapter recordings into a single continuous track so listeners can play the entire book through their media player without manually navigating between dozens of separate files. Trim the lead-in silence from each chapter for tight transitions.
Crafting a Crossfade DJ-Style Continuous Mix
Set crossfade to two or three seconds and the merger overlaps each track transition using an equal-power curve, creating a seamless continuous mix that sounds like a live DJ set. Trim each song to start at the first beat and end right before the fade-out for the tightest possible mix.
Combining Lecture and Course Recordings
University professors and online course creators often record lectures in segments due to breaks, equipment restarts, or topic changes. Upload all the segments, trim the dead air from the start and end of each one, and merge into a single file that students can play through without managing multiple recordings.
Merging Interview Clips Into a Highlight Reel
Journalists and content creators can upload full interview recordings, use the per-file trim to extract only the best quotes and soundbites from each one, and merge those highlights into a single polished clip for social media, a website, or a news segment.
Building a Medley or Mashup From Multiple Songs
Trim each song to its most recognizable section (chorus, hook, or bridge), arrange them in the order that flows best, enable a 1-second crossfade, and merge into a single medley track. Useful for dance performances, talent shows, and personal creative projects.
Combining Voice Memos Into a Single Reference Recording
People who record thoughts, meeting notes, or brainstorm sessions as short voice memos throughout the day can upload all of them at once, trim any trailing silence, and merge into a single chronological recording for transcription or archival.
How It Works
Select and Upload the Audio Files
Choose two or more files from your device at once, or drag a batch directly onto the upload zone. The tool accepts MP3, WAV, FLAC, OGG, M4A, and AAC. Mix formats freely within the same merge. Each file is decoded using the Web Audio API to display its duration.
Trim Each Track to the Section You Want
Every track shows start and end time inputs. Set custom values to include only the portion you need. A clip of 0 to 5.2 seconds from the first track and 10 to 45 seconds from the second is perfectly fine. Leave the defaults to use the full file.
Arrange the Playback Sequence
Use the up and down arrows to change track positions. The file at the top of the list plays first, the one at the bottom plays last. The visual order you set here becomes the audible order in the merged output.
Set Crossfade and Merge
Choose zero for a clean hard cut between tracks, or one to three seconds for an overlapping blend. Press the merge button, wait while the server stitches everything together, and download the resulting MP3. Preview the merged file to confirm the order and transitions sound the way you intended.
Merge Like a Professional
Trim Dead Air Before Merging
Use the start and end time inputs on each track to cut leading silence, trailing silence, and unwanted sections. The per-file trim runs in your browser and only the trimmed portion is sent to the server. This produces tighter transitions than merging full files and trimming afterward.
Number Your Filenames Before Uploading
Rename files with a numeric prefix like 01-intro.mp3, 02-verse.mp3, 03-chorus.mp3 before dragging them in. Most operating systems auto-sort by name, which means less manual reordering after upload.
Match Loudness Levels Before Merging
If certain tracks are noticeably quieter or louder than others, run them through our Audio Volume tool first to bring everything to a consistent level. Even loudness across all source files makes the merged output sound cohesive rather than patched together.
Crossfade for Music, Hard Cuts for Speech
A two-second crossfade blends songs beautifully but can make spoken segments overlap and become unintelligible. For podcast assembly and audiobook merging, set crossfade to zero so words at the boundary remain clean and distinct.
Use Lossless Sources When Available
If you have the original WAV or FLAC recordings, upload those instead of MP3 copies. Merging from lossless sources avoids stacking lossy compression artifacts. The server encodes the output once to MP3, producing a cleaner result than re-encoding already-compressed files.
Preview Each Track Before Pressing Merge
Every track in the list has an inline audio player. Listen through the sections you plan to include, especially the boundaries, to make sure you set the trim points where you intend. A few seconds of previewing prevents a round trip of re-uploading and re-merging.
Check the Estimated Duration Before Merging
The settings bar shows the total estimated output duration after accounting for trim ranges and crossfade overlap. If the number looks too long or too short, adjust your trim points before pressing merge rather than waiting for the result.
Chain With Other Audio Tools for a Complete Pipeline
Extract audio from video with Video to MP3, adjust volume with Audio Volume, trim individual files here with the built-in controls, then merge into one output. Chaining tools lets you optimize every step of the pipeline without installing desktop software.