YouTube SpeedUp is a Firefox extension designed to give users enhanced control over video playback speeds on YouTube. This subscription-based tool integrates seamlessly into the Firefox browser, requiring no additional permissions or data collection. Once installed, users can easily adjust playback speeds using a simple speedometer icon that appears in the video player controls. The extension allows speed adjustments in increments of 0.25, with a broad range from 0.25× to 16×, making it ideal for those who prefer to accelerate or decelerate their viewing experience.

The functionality of YouTube SpeedUp extends across different videos and supports keyboard interactions, ensuring accessibility for all users. It retains the last used speed setting locally, allowing for a consistent experience when switching between videos. The extension is designed for desktop use on Firefox version 115 and above, and it is not compatible with mobile devices. Overall, YouTube SpeedUp provides a user-friendly and efficient way to customize video playback, enhancing the overall multimedia experience.