Crescendo — Tab Volume Booster by Darren

Some videos are just too quiet. Crescendo adds a real volume boost on top of your system volume — up to 1200% (12× louder) — so you can finally hear that quiet lecture, podcast, interview, or video call without cranking your speakers into distortion. It works the other way too: pull any tab down below 100% when it's blasting.

What you can do:
• Boost any tab up to 1200% — 12× its normal volume
• Lower a too-loud tab below 100%
• Fine control: 1% steps below 100%, quick 10% jumps above — with the slider or your arrow keys
• Voice preset — cuts through muddy audio so speech is clear and up-front
• Bass preset — adds weight and warmth to music
• The toolbar icon shows each tab's current volume at a glance

Built to sound good, not just loud. A smooth soft-clipper rounds off the loudest peaks instead of letting them turn harsh and buzzy, so even big boosts stay listenable.

Private by design. Crescendo collects no data, has no trackers, and never talks to a server. All audio processing happens locally in your browser using the Web Audio API.

Good to know: works great on YouTube, Spotify Web, and most video and news sites. Because of browser security, DRM-protected streams (e.g. Netflix) and some cross-origin embedded players can't be boosted above 100% — Crescendo tells you when that's the case.