How to combine podcast segments into one episode — free
- Step 1Gather your segments — Export each segment from your recording app: intro music, the interview/main, any ad reads, the outro. Any of
MP3, WAV, FLAC, M4A, OGG, Opusworks — they don't need to match. - Step 2Drop them in episode order — Add the segments to the dropzone in the order they should play: intro first, outro last. The file list shows each segment's duration — sanity-check the running order and total length.
- Step 3Decide on crossfade — For a clean cut between segments, leave crossfade at 0. For a smooth blend, set a crossfade — but remember it only applies to exactly 2 segments. For a 4-segment episode, either accept hard cuts or merge in pairs (intro+main, then +ad, then +outro).
- Step 4Choose output format — MP3 (192 kbps) is the standard for podcast feeds and is the default. Pick WAV or FLAC if you'll master the episode before final export; pick M4A for Apple-centric workflows.
- Step 5Run the merge — FFmpeg-WASM normalises every segment to 48 kHz stereo, concatenates in order, and encodes one file — all locally. Long interviews mean longer processing since it runs on your CPU.
- Step 6Download and level the episode — Save
merged.mp3. Because segments were recorded separately, levels will differ between them — finish with loudness-normalizer at -16 LUFS (Apple/Spotify target) so the whole episode sits at one consistent loudness.
Typical podcast segments and how they merge
A real episode is several segments captured separately. The merger reconciles their formats automatically.
| Segment | Common source format | Merge behaviour |
|---|---|---|
| Intro music / sting | MP3 or WAV, 44.1 or 48 kHz | Resampled to 48 kHz; can crossfade into segment 2 |
| Interview / main | Zoom/Riverside export, often 48 kHz | Joined as-is on the 48 kHz timeline |
| Mid-roll ad read | Locally recorded WAV | Concatenated in place at list position |
| Outro / call to action | MP3, sometimes mono | Mono upmixed to stereo, joined last |
Merge controls for a podcast episode
The two real controls. Crossfade is limited to two-segment merges.
| Control | Recommended for podcasts | Note |
|---|---|---|
| Crossfade (s) | 0 for segment joins; 1-3 only for an intro-music blend | Applies only when exactly 2 files are merged |
| Output format | MP3 (feed) or WAV (master first) | MP3/M4A fixed at 192 kbps; WAV/FLAC lossless |
| Order | Intro -> main -> ad -> outro (top to bottom) | No reorder handle; remove + re-add to fix |
| Loudness | Normalise after merge, not in the merger | Use loudness-normalizer at -16 LUFS |
Tier limits for episode-length audio
A full interview easily exceeds the Free duration cap, so episode assembly typically needs Pro or higher.
| Tier | Max file size | Max duration / file | Files per batch |
|---|---|---|---|
| Free | 50 MB | 30 min | 1 |
| Pro | 200 MB | 120 min | 10 |
| Pro-Media | 100 GB | Unlimited | 100 |
| Developer | 100 GB | Unlimited | Unlimited |
Cookbook
Real episode builds with segments, options, and output. Levels still differ between segments after merging — normalise as the final step.
Standard 4-segment episode (hard cuts)
Intro, interview, ad, outro joined end-to-end. Crossfade left at 0 because it only works for 2 files.
Inputs (in order): intro.wav 48000 Hz 2ch 0:12 interview.mp3 44100 Hz 2ch 47:30 adread.wav 48000 Hz 1ch 0:45 outro.mp3 44100 Hz 2ch 0:20 Options: crossfade 0, format MP3 Output: merged.mp3 48000 Hz 2ch 48:47 (192 kbps) Next: loudness-normalizer -> -16 LUFS
Crossfade music intro into the first words
For a radio-style blend, merge just the intro music and the main segment with a short crossfade — that's a 2-file merge, so crossfade applies.
Inputs: intro-music.mp3 0:10 main.mp3 42:15 Options: crossfade 2.0, format MP3 Output: merged.mp3 ~42:23 (music fades into speech over 2s) Then add ad + outro in a second hard-cut merge.
Assemble a multi-part remote interview
The connection dropped twice, so the interview is in three files. Join them in order, then add intro/outro.
Step 1 combine-podcast-segments-free part1.mp3 + part2.mp3 + part3.mp3 -> interview-full.mp3 Step 2 combine-podcast-segments-free intro.wav + interview-full.mp3 + outro.mp3 -> episode.mp3
Master before publishing
Output WAV from the merge so the master stays lossless until the final MP3 export.
Step 1 combine-podcast-segments-free segments -> episode.wav (format WAV) Step 2 podcast-master episode.wav -> leveled + limited Step 3 bitrate-changer (if needed) -> 128 kbps mono-friendly feed MP3
Trim guest silence before joining
Long pauses while a guest reconnected leave dead air. Trim each segment first so the episode flows.
Step 1 audio-trimmer cut the 40s reconnect gap out of part2.mp3 Step 2 combine-podcast-segments-free intro + part1 + part2-trimmed + outro -> episode.mp3
Edge cases and what actually happens
Segments have different volume levels
ExpectedThe merger joins audio as-is; it does not balance loudness between segments. A quiet guest mic next to a loud intro stays uneven. This is by design — run loudness-normalizer (target -16 LUFS) on the merged episode, or per-segment first if levels are very far apart.
Crossfade ignored on a 4-segment episode
IgnoredCrossfade applies only when exactly 2 files are merged. A full episode (intro + interview + ad + outro) joins with hard cuts even if you set a crossfade. To blend the intro music specifically, do a separate 2-file merge of intro + main with crossfade, then add the rest.
Only one segment provided
RejectedThe merger needs 2+ files (Audio merger needs at least 2 files.). If your episode is a single recording that just needs cleanup, skip the merger and go straight to audio-trimmer or podcast-master.
Mixed sample rates (Zoom 44.1k + local 48k)
By designRemote-recording exports vary in sample rate. The merger resamples everything to 48 kHz before joining, so there's no pitch shift or clock drift across the seam between a 44.1 kHz and 48 kHz segment.
A segment is mono
ExpectedA mono ad read or phone-recorded outro is upmixed to stereo on the common timeline, so the episode is stereo throughout. If your feed expects mono, downmix the final file with a converter after merging.
ID3 chapter markers / artwork not preserved
DroppedRe-encoding writes a fresh stream, so any input chapter markers, episode artwork, or ID3 tags are not carried over. Add episode metadata and cover art afterward with id3-editor.
Interview exceeds the Free 30-minute cap
BlockedFree caps each file at 30 minutes / 50 MB — most full interviews are longer. Pro raises it to 120 min / 200 MB / 10 files; Pro-Media/Developer remove the duration limit. The 30-min cap is per input segment.
Free tier batch is 1 file
Tier limitEpisode assembly needs at least 2 segments, but Free's audio batch is 1 file. Practical episode merging starts at Pro (10 files). The processing is identical; only the file-count and size gates change.
Gaps between segments sound abrupt
By designA hard join is gapless at the seam, but trailing/leading silence inside segments creates audible pauses. Trim segment ends with audio-trimmer, or use fade-in-out for smoother starts/ends, before merging.
Long episode is slow to process
ExpectedA 90-minute episode is fully decoded, resampled, and re-encoded in the browser, which takes time and memory. Output FLAC instead of WAV to reduce output size, and close other tabs during the run.
Frequently asked questions
Can I combine segments recorded at different sample rates?
Yes. The merger resamples every segment to 48 kHz stereo before joining, so a 44.1 kHz Zoom export and a 48 kHz local recording combine seamlessly with no pitch shift or seam click. This is the main reason it works where command-line concat fails on mismatched inputs.
Does it balance the volume between my segments?
No — the merger only joins audio, it doesn't level it. Segments recorded separately will have different loudness. After merging, run loudness-normalizer at -16 LUFS (the Apple Podcasts/Spotify target) so the whole episode is consistent. podcast-master bundles leveling and limiting in one pass.
Can I crossfade between all my segments?
Only between two. The crossfade applies when exactly 2 files are merged; with 3+ segments it's ignored and a hard cut is used. The common pattern is to crossfade just the intro music into the main segment as a separate 2-file merge, then add the remaining segments with hard cuts.
Are my unreleased episodes uploaded anywhere?
No. The entire merge runs in your browser on FFmpeg 8.1 (WebAssembly). Episode audio and guest recordings never leave your device — important for embargoed interviews and NDA'd guests. There's no server processing.
What output format should I use for my podcast host?
MP3 at 192 kbps (the default) is the safe choice for every host. If you master the episode first, output WAV or FLAC from the merge to stay lossless, then export the final MP3 (and re-target bitrate with bitrate-changer if your host wants 128 kbps or mono).
Will my episode artwork and chapter markers survive?
No. The merge writes a fresh audio stream, so input ID3 tags, chapter markers, and embedded artwork are dropped. Add title/artist/episode metadata and cover art afterward with id3-editor.
How long can my interview segment be?
On Free, 30 minutes max per file — most interviews exceed that. Pro allows 120 minutes per file (and 10 files / 200 MB); Pro-Media and Developer remove the duration limit (100 GB). The duration cap is per segment, separate from the size cap.
What order will the segments play in?
The order they appear in the file list, which is the order you added them. There's no drag-to-reorder. Lay them out intro-to-outro when you drop them; if the order is wrong, remove a segment with its X and re-add it in the right place.
My interview dropped and recorded in three parts — can I rejoin it?
Yes. Drop the three parts in order and merge them into one continuous interview file, then do a second merge to add your intro and outro around it. Trim any reconnect dead-air with audio-trimmer first.
How many segments can I merge at once?
At least 2. Pro allows 10 files per batch, Pro-Media 100, Developer unlimited. Free's audio batch limit is 1 file, so episode assembly needs Pro or higher.
Can I remove silence between segments while merging?
Not in the merger itself. For internal pauses, use silence-stripper on a segment before merging; for trailing/leading dead air, use audio-trimmer. The merge then joins the cleaned segments gaplessly.
What's the recommended end-to-end workflow?
Trim dead air per segment, merge segments into one episode here (output WAV if mastering), then level the whole thing with loudness-normalizer or podcast-master, and export the final MP3. Add metadata with id3-editor last.
Privacy first
Every JAD Audio tool runs entirely in your browser via FFmpeg (WebAssembly) and RNNoise. Your audio files never leave your device — verified by zero outbound network requests during processing.