f.lux
Screen color temperature app in Productivity & writing
People recommend f.lux for shifting screen colors warmer at night, which many find eases eye strain and helps them sleep. Some find it too basic, and others say it does not help them.
11 people recommended f.lux in Hacker News comments, 1 had mixed feelings and 10 criticized it, November 2025 to October 2026.
Summary written by Claude from 24 comments. It was written before the November 2026 recount, and 23 of those comments still count.
22 people gave an opinion
- recommend it
- 11
- mixed feelings
- 1
- warn against or regret it
- 10
The record
Recommended in 9 of 12 months
In 11 different threads.
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: recommended
- March 2026: recommended
- April 2026: recommended
- May 2026: not recommended
- June 2026: recommended
- July 2026: not recommended
- August 2026: recommended
- September 2026: not recommended
- October 2026: recommended
Why it doesn’t carry the badge
- 11 people recommend itNeeds 10 or more, met.
- 1.1 recommenders for every criticNeeds 2 to 1 or better, not met.
- Recommended in 9 of 12 monthsNeeds 4 or more, met.
- Recommended in 11 threadsNeeds 5 or more, met.
- The biggest thread supplies 18% of its recommendersNeeds half or less, met.
The same rules apply to every product, and the badge can’t be bought. Mixed feelings count toward neither side. How the badge works
What people say about it
Reasons grouped from a sample of 22 of the 24 opinions about it, picked in proportion to how many people recommend it, have mixed feelings and criticize it. Each mark is one comment in the sample. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Warmer screen tint at night
“Shifting the white point is far more comfortable than dark mode for me.”
Comment from 17 Jan 2026 in “Light Mode InFFFFFFlation” “not only has warmer tinting but also "Darkroom mode" (red only”
Comment from 9 Apr 2026 in “Ask HN: Would you buy a red-pixel only screen?” “with f.lux/redshift the blue light is ok”
Comment from 21 Dec 2025 in “I can't upgrade to Windows 11, now leave me alone” - Comment from 22 Mar 2026 in “No evidence cannabis helps anxiety, depression, or PTSD”
Helps sleep and bedtime
“It was extremely helpful to me, to the point where I could pinpoint basically all my insomnia nights”
Comment from 31 Jul 2026 in “I built a f.lux alternative because the M5 Max firmware broke existing solutions” “my sleep quality got much better when I turned on f.lux”
Comment from 21 Feb 2026 in “Blue light filters don't work” “Helped me start going to bed at 10pm”
Comment from 15 Apr 2026 in “Good Sleep, Good Learning (2012)” Long-time reliable daily use
“That saved my eyes like 15 years ago whenever I found it”
Comment from 27 Oct 2026 in “New iMac with M6” “used to be one of my fav apps”
Comment from 2 Jun 2026 in “Adafruit Receives Demand Letter from Fenwick Legal Counsel on Behalf of Flux.ai” Free and adjustable settings
“Fantastic piece of software.”
Comment from 31 Aug 2026 in “Study: Blue light impairs the eye's ability to distinguish fine detail most”
What people warn about
Each mark is one comment
Breaks at high latitudes
“setting the profile automatically breaks down at high latitudes”
Comment from 8 Nov 2025 in “Dark mode by local sunlight (2021)” “it actually makes seasonal changes so much worse”
Comment from 8 Nov 2025 in “Dark mode by local sunlight (2021)” Night shift issues remain
“f.lux has had an issue filed for more than 6 weeks with the solution being wait it out until Apple fixes it”
Comment from 2 Aug 2026 in “I built a f.lux alternative because the M5 Max firmware broke existing solutions” “night shift issues which are still present in f.lux”
Comment from 31 Jul 2026 in “I built a f.lux alternative because the M5 Max firmware broke existing solutions” Some find it ineffective
“I've noticed if I use the f.lux feature for just 15 minutes I begin to get tired at night.”
Comment from 9 Aug 2026 in “Melatonin impairs morning cognition in healthy young adults” “Deemed it not helpful for myself”
Comment from 31 Jul 2026 in “I built a f.lux alternative because the M5 Max firmware broke existing solutions”
What people said
22 of the 24 opinions about it, picked in proportion to the three counts, newest first. Each links to the original comment.
“That saved my eyes like 15 years ago whenever I found it”
“works even better than f.lux when I'm working in an environment where I can't control the ambient lighting”
“We may choose to buy or sell assets…”
“Fantastic piece of software.”
“I've noticed if I use the f.lux feature for just 15 minutes I begin to get tired at night.”
“f.lux has had an issue filed for more than 6 weeks with the solution being wait it out until Apple fixes it”
“It was extremely helpful to me, to the point where I could pinpoint basically all my insomnia nights”
“Deemed it not helpful for myself”
“The website looks like 50 other AI-generated product sites I've seen lately.”
“night shift issues which are still present in f.lux”
“used to be one of my fav apps”
“Helped me start going to bed at 10pm”
“not only has warmer tinting but also "Darkroom mode" (red only”
“F.lux is fairly intrusive.”
“use redshift/f.lux/etc on screens”
“my sleep quality got much better when I turned on f.lux”
“no way im using something basic like f.lux”
“Shifting the white point is far more comfortable than dark mode for me.”
“with f.lux/redshift the blue light is ok”
“because it's the better "dark mode" anyway (IMO”
“setting the profile automatically breaks down at high latitudes”
“it actually makes seasonal changes so much worse”
Counts come from 1,791,911 Hacker News comments labeled by Claude, November 2025 to October 2026, with data through October 31, 2026. Counts updated 2 Nov 2026. How we count. Report a mistake.