Volume Adjuster

How to Use

1. Click the area above to select a file, or drag and drop a file onto the page
2. Adjust parameters in the settings area
3. Click the process button and download the result when ready

Frequently Asked Questions

How It Works

The Volume Adjuster uses FFmpeg WebAssembly with the volume and afade audio filters to modify audio amplitude. The volume filter applies a gain multiplier to each PCM sample: output = input × gain_factor.

Volume adjustment is measured in dB (decibels) or percentage. Doubling volume = +6dB = 200%. The filter supports gain from -infinity (silence) to +20dB. Values above 0dB (100%) amplify quiet audio, while values below 0dB attenuate loud audio. The tool uses floating-point sample processing to prevent clipping — values exceeding 0dBFS are limited to prevent distortion.

Fade effects are applied using the afade filter with configurable duration and curve type (linear, exponential, logarithmic). Fade-in ramps from silence to full volume; fade-out ramps from full volume to silence. Both effects are time-aligned using the audio's total duration for perfectly synchronized transitions.

Tips & Best Practices

• 200% is usually enough: If your audio needs more than 200% amplification, the source is likely too quiet and should be normalized instead.
• Avoid clipping: Amplifying past 100% without monitoring can cause distortion. Use the waveform visualizer to check peaks.
• Fade in/out for podcasts: 0.5-1 second fades at the start and end create a professional, polished sound.
• Combine with normalize: For consistently loud audio, boost volume first, then normalize to target loudness.
• Check before and after: Listen to a sample of the output to ensure no distortion was introduced.
• dB vs percentage: +6dB doubles the volume, +3dB increases by ~41%. Use dB for precision, percentage for simplicity.

Use Cases

Podcast producers boosting quiet voice recordings captured with distant microphones to broadcast-ready loudness levels.

Music producers adjusting volume levels of individual tracks before mixing them together. Video creators balancing audio levels in screen recordings where the microphone input was too quiet. Lecture archivists normalizing inconsistent volume across multiple recording sessions. Voicemail archivists boosting quiet voicemail recordings for better intelligibility. Content creators adding fade-in to audio intros and fade-out to outros for smooth transitions.

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