Penumbra is a smart theme controller for Chrome. It adapts every website to your ideal appearance — intelligently, per-site, on your schedule.
Penumbra goes beyond a simple toggle. It understands each website and applies intelligent transformations.
Smart Dark forces dark mode intelligently. Smart Light ensures bright pages. Auto follows your system preference. Each mode adapts to the site rather than blindly inverting.
Control brightness, contrast, and sepia per website. Your settings are remembered for each domain.
Enable or disable Penumbra for individual domains. Each site gets its own theme configuration.
Set dark mode to activate automatically in the evening and disable in the morning. Your eyes will thank you.
Add Penumbra to Chrome from the Web Store. No account, no setup, no configuration.
Penumbra activates automatically. Every website adapts to your system theme preference.
Fine-tune any site with brightness, contrast, sepia controls. Your settings are remembered.
Join thousands of users who browse in comfort. Penumbra is free, private, and works everywhere.
Install Penumbra