# f.lux

The original blue-light filter — free software that warms your screen’s color temperature after sunset and shifts back to daylight in the morning, based on your location.

- **Category:** [Health](https://notchlist.vercel.app/category/health/)
- **Price:** Free
- **Open source:** no
- **Official site:** https://justgetflux.com/
- **Available via:** Direct
- **Requirements:** macOS; specific minimum version not published on the developer’s site.
- **Maker:** f.lux Software LLC

## Kitsmith's take

f.lux predates macOS’s built-in Night Shift by years and is often the app people mean when they say “blue light filter.” It sets your location once, then automatically warms the display after sunset and returns it to normal in the morning, with manual lighting-profile presets available too. No Mac App Store version — Apple’s sandboxing rules have historically blocked this kind of low-level color control from being App Store-distributable, per the developer. Free for macOS, Windows, and Linux.

## Features

- **Location-based scheduling:** Set your location once and f.lux automatically warms the display at sunset and restores it at sunrise.
- **Manual lighting profiles:** Tell f.lux what kind of indoor lighting you have for a more accurate warm-color match.
- **Per-app disabling:** Temporarily disable the effect for color-sensitive work like photo or video editing.
- **f.luxometer:** A companion tool for measuring the actual spectral output of your display and other light sources.

## FAQ

**Is f.lux free?**

Yes — free for macOS, and also free for Windows (personal use) and Linux.

**How is f.lux different from Night Shift?**

They solve the same problem with a similar approach; f.lux predates Night Shift and adds location-based scheduling, lighting profiles, and per-app disabling that Night Shift doesn’t offer.


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Hand-verified listing on Kitsmith: https://notchlist.vercel.app/apps/flux/