What SOUNDLOOPER Can Do
A tool specialized for the "creating loop material" step in ambient and sound effect production workflows. Handle pre-processing before importing to your DAW, or create looping audio for web content - all within your browser.
Automatic Loop Point Detection
Automatically detects up to 10 naturally loopable sections using RMS envelope similarity analysis and zero-crossing point alignment.
Loop Compatibility Score
Automatically evaluates "naturalness if looped as-is" right after loading. Quantifies start/end volume differences, waveform connection smoothness, and tonal balance.
Customizable Analysis Modes
Combine 3 anchor modes (fix start, fix end, auto scan) with 2 detection priorities (quality, length) to find loop points that match your goals.
Loop Preview Playback
Preview each detected candidate with one-click loop playback. Listen to the actual looped result and choose the optimal point.
Multi-Format Export
Supports 3 formats: WAV (uncompressed PCM), OGG (Opus / 128-320kbps), and AAC (M4A). Export in the optimal format for your use case.
Privacy-Conscious Design
All processing is done within the browser. Audio files are never uploaded to any server. Fully local processing with no external communication.
Usage Guide
1Load an Audio File
Drag and drop an audio file onto the drop area in the center of the screen, or select a file using the "Open File" button in the upper right. Supports major audio formats including WAV, MP3, AAC, OGG, and FLAC.
Once loading is complete, the waveform is displayed and the Loop Compatibility Score automatically appears in the toolbar. This score evaluates how naturally the audio would loop from head to tail in its current state, based on three axes: volume difference between start/end points, smoothness of waveform connection, and tonal balance between the beginning and end.
A high score (green) means the audio loops fairly naturally as-is. A low score can often be greatly improved by trimming, so proceed to the next step.
2Choose Analysis Settings
In the "Analysis Settings" panel at the bottom left, choose the detection method that suits your purpose.
Anchor Point determines whether to search based on the loop start or end point. "Fix start point" searches for the loop end from near the beginning. "Fix end point" searches for the start from near the end. "Auto" flexibly scans both to find the optimal combination.
Priority Mode has two options. Quality priority ranks candidates with higher scores (more natural connections) at the top. Length priority suggests the longest sections within an acceptable score range - useful when you want to preserve as much of the original length as possible.
3Run Loop Analysis
Once settings are configured, press the "Analyze Loops" button. When analysis is complete, up to 10 candidates are listed by score (or loop length) in the "Loop Point Candidates" panel at the bottom center.
Each candidate displays the loop section's start time, end time, length, ratio to the original audio, and whether Zero-Cross Alignment is applied. Score colors are visually distinguished: green (high), blue (medium), and purple (low).
4Verify with Loop Preview
Press the play button on the right side of each candidate to loop-play that section. Listen to the actual looped audio to check for click noise or unnatural breaks at the connection point.
Click the candidate row itself to apply that section as the selection range in the waveform editor. You can also fine-tune by manually dragging the handles.
5Trim and Export
Once the selection range is finalized, press "Cut to Selection" in the toolbar to trim the audio so only that section remains. After cutting, the Loop Compatibility Score is automatically re-evaluated, so you can verify the improvement.
From the "Export" panel on the bottom right, export in 3 formats: WAV, OGG, or AAC. OGG bitrate is selectable from 4 levels (128k-320k). Export range can be switched between "Selection" or "Full."
Trimming is non-destructive. You can always restore the original audio with the "Reset" button. Feel free to experiment.
Keyboard Shortcuts
| Key | Features |
|---|---|
| Space | Play / Pause |
| Escape | Stop |
| L | Toggle Loop Playback |
| J | Seam Check Playback |
| Ctrl + A | Select All |
| Ctrl + Wheel | Zoom In/Out Waveform |
| Wheel | Scroll Waveform |
| Shift + Drag | Scroll Waveform (Mouse) |
Supported Formats
Lossless · Highest Quality
Ideal for DAW import
128 / 192 / 256 / 320 kbps
Ideal for loop playback
High-efficiency compression (M4A)
For iOS / Mobile
Input supports all formats decodable by the browser Web Audio API, including WAV, MP3, AAC, OGG, and FLAC.
Frequently Asked Questions
Disclaimer
Please note the following regarding the use of this tool (SOUNDLOOPER).
- This tool is provided "AS IS" without any warranty regarding completeness, accuracy, or fitness for a particular purpose.
- The developers and operators shall not be liable for any damages arising from the use of this tool, including but not limited to data loss, lost profits, or business interruption.
- Automatic loop point detection is based on waveform analysis estimation and does not guarantee optimal loops for all audio sources. Final quality judgment is the responsibility of the user.
- Copyright of audio files belongs to their respective rights holders. When using audio edited with this tool, please comply with copyright law and other relevant regulations.
- OGG (Opus) and AAC encoding depends on the browser built-in MediaRecorder API, so output quality may vary depending on the browser and OS.
- All audio processing in this tool is done client-side (within the browser). Audio data is not sent to external servers, but browser behavior and security follow the browser vendor policies.
- This Disclaimer may be changed without prior notice.
Operated by AMIX Design Studio (ASOBOAD)