Freeware v4.141 ✓ Checksum Published

Download f.lux for Windows PC v4.141 for Windows PC

Name: f.lux for Windows PC
Availability: InStock
Author: Flux Software LLC

f.lux warms your screen after sunset and restores daylight colour in the morning, automatically following your location and lighting so late-night PC use...

⬇ Direct Download (0.7 MB)

Technical Specifications & System Requirements

Developer Flux Software LLC

Platform & OS Windows 10 / 11 (64-bit)

Package Size 0.7 MB

Architecture x64 (64-bit)

Package Format EXE Installer

Security Verification SHA-256 checksum published

SHA-256 Cryptographic Checksum Computed from the file we serve

              5d8a0229336f8aa70462c5397c055a446dd396c319f7310e698a31f05903521a
            

              $ Get-FileHash .\f-lux-pc.exe -Algorithm SHA256
            

Software notes

The Bottom Line: f.lux remains the reference point for automatic screen warming, and the reason is how completely it disappears into the background once configured. Set your location once and the transition at sunset is gradual enough that you stop noticing it within a day or two, while working late stops feeling like staring into a headlight. The v4 feature set is genuinely thoughtful: disabling f.lux per application means Photoshop or video work is never ruined by an orange cast, the bedtime mode pushes colour warmer in stages rather than in one jarring jump, and the display analysis that estimates how much light your screen is emitting is something Windows Night Light simply does not attempt. Be clear about the licensing before you install it everywhere, though: f.lux is free for personal use only, and offices need the paid Corporate Edition, which is a separate build with site licensing. Colour-critical workers will also find the warm cast is something they schedule around rather than live with, and the interface, while functional, still feels like a utility from an earlier Windows era. Windows 10 and 11 now ship a basic Night Light feature, but it lacks f.lux's location-aware scheduling, per-app rules and smart-light integration. For anyone who regularly works after dark on a personal PC, f.lux is still the more complete and more considerate tool.

Features

The sunset transition is automatic and gradual, following your real location and local sunrise and sunset times rather than a fixed clock schedule you must maintain yourself.
Per-application disable rules let you keep accurate colours in Photoshop, video editors and games while every other program stays warm in the evening.
Bedtime mode, presets and colour filters give far finer control over colour temperature, down to very warm candle-like levels, than the basic Night Light built into Windows.
Optional Philips Hue and LAN smart-light integration can shift your room lighting together with your screen, which makes the whole workspace feel calmer at night.
The installer is tiny, installs in seconds, uses negligible system resources in the background and contains no advertising, bundles or upsell nagging in personal use.

Considerations

It is free for personal use only, so using this standard build across a business requires the separate paid Corporate Edition and site licences instead.
Any colour grading, photo editing or design work done while f.lux is active will be misleading, so colour-critical users must remember to disable it first.
The settings window and tray menus are dated and occasionally confusing, with useful options such as per-monitor behaviour buried deeper than they should be.

About & Overview: f.lux for Windows PC

f.lux adjusts your display's colour temperature to match the time of day: bright and neutral like daylight while you work, then gradually warmer and softer after sunset so your screen matches indoor lighting instead of glaring like the sun at midnight. Tell it where you live and what lighting you use, and it handles sunrise and sunset transitions automatically. Beyond the basic schedule it offers a bedtime mode that warms the screen further before sleep, presets and colour filters, per-app disable rules for colour-sensitive work, hotkeys, a backwards alarm clock that warns you not to stay up late, and optional integration with Philips Hue and other smart lights. It is free for personal use on Windows; businesses need the paid Corporate Edition.

How to Install & Verify f.lux for Windows PC

STEP 1

Download the official installer

Download the small f.lux setup program (flux-setup4.exe) from justgetflux.com using the button above and save it to your Downloads folder.

STEP 2

Run the installer

Double-click the downloaded EXE and approve the Windows prompt; the lightweight installer sets f.lux up in your user profile without extra bundled software or toolbars.

STEP 3

Finish and launch

When f.lux starts, enter your location so it can calculate local sunrise and sunset, then use the tray icon to preview the night colour and adjust the daytime and night temperatures to taste.

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Frequently Asked Questions & Verification Guide

Is f.lux available for Windows?

Yes. f.lux runs on Windows 7, 8, 10 and 11, and the current version listed here is 4.141 from Flux Software LLC. Once installed it sits in the system tray and adjusts your display's colour temperature automatically based on your location and the time of day.

Is f.lux free?

For personal use on your own Windows PC it is completely free, with no time limit. The paid product is the separate Corporate Edition, which businesses buy for site licensing and central deployment.

Is f.lux better than Windows Night Light?

They do the same basic job at different depths. Night Light offers a manual schedule and a single warmth slider, while f.lux calculates sunrise and sunset from your location, adds a staged bedtime mode, per-app and per-monitor disable rules, colour presets, hotkeys and smart-light integration. If you only want a slight warm tint on a timer, Night Light is enough; f.lux is the more complete tool.

What is the latest version of f.lux?

Version 4.141 is the current f.lux release listed on this page, from Flux Software LLC.

Does f.lux actually work?

The technical part is real and easy to verify: f.lux measurably shifts your display towards warmer colours in the evening, reducing the amount of blue-heavy light you get after sunset, and it can even estimate how much light your screen is emitting. Whether that improves your sleep is a personal matter, but the colour change itself does exactly what it claims.