Disclaimer
Last updated: October 11, 2026
Black Screen Online is a free set of screen tools at blackscreenonline.com, run by one person, Ali Usman. This page explains what the tools and guides are for, where their limits are, and who to ask when you need expert help. Everything on Black Screen Online is general information to help you use your screen. It is not professional advice.
Health and safety
Is Black Screen Online medical advice?
No. Black Screen Online's guides about sleep, eye strain, light and night vision are general information, and the sources behind them are linked in the text. They are not a diagnosis or a treatment. Black Screen Online's color tools are not medical light-therapy devices, and they are not designed or tested to deliver a treatment.
For a health concern, please speak to a doctor or an eye-care professional, and don't delay or ignore their advice because of something you read here. If a symptom is sudden or severe, such as a seizure, get emergency help right away.
Is Black Screen Online safe if flashing light affects you?
Most of Black Screen Online's tools fill your screen with one steady color, such as black or white. A few tools change the screen on purpose, and here is exactly what they do:
Flash blinks the whole screen on and off, up to 3 times a second. It runs only in full screen, it asks you to confirm before it starts, and it never turns on by itself: every new visit starts without it.
Pulse dims the screen and brings it back slowly, about once every 4 seconds. It changes brightness gradually instead of switching sharply between light and dark.
Screensaver scenes show slow movement, such as falling snow, drifting stars or a clock that glides across the screen. One scene shifts the whole screen slowly through very dark colors.
Even at these speeds, flashing or changing light may affect people who are sensitive to it, so no flashing effect can be guaranteed safe for everyone. Please skip Flash if flashing light affects your health, for example if you have photosensitive epilepsy. If any screen makes you feel unwell, look away and close it. Any new tool that can flash will also ask you first.
What the tools are for
What are Black Screen Online's tools not for?
Black Screen Online's tools are made for everyday screen jobs. Please don't use them for these:
- Light therapy or any medical use. The tools are not designed or tested as medical devices.
- Exact color work. The tools send exact colors, but they can't measure what your screen shows. Color work that must be exact needs a hardware calibration device.
- Deciding a repair or warranty claim. A screen test can help you find a problem, such as a dot that stays lit, but it can't fix the hardware. For repairs, contact the device maker or a repair shop.
- Locking or hiding your device. A black screen only covers the display. Your device keeps running underneath, and anyone who touches it can bring the page back.
- Alarms where a miss could cause harm. Clocks, timers and alarms need the page to stay open, and sleep mode or a battery saver can stop them.
How should you read what the tools show?
What you see depends on your screen as much as on Black Screen Online. The tools use the exact color code listed, such as #000000 for pure black, but each screen shows that color in its own way, based on its type, brightness and settings. A screen test can show a possible problem, but it can't confirm the cause. A qualified repair technician can find the cause, and the device maker or warranty provider decides what a warranty covers. Notes about battery life and screen marks (burn-in) depend on the kind of screen you have.
How can you look after your eyes and your device?
A few simple habits help when you use Black Screen Online, and your device maker's advice always comes first:
- Turn the brightness down in a dark room, because a bright screen can feel harsh.
- Take a break if your eyes feel tired, and look at something far away.
- Clean a screen the way your device maker says, not with anything stronger.
- Check your device maker's advice before leaving the same image on a screen for many hours.
About the content
How accurate are the guides?
I check Black Screen Online's guides against reliable sources and link those sources in the text, but a guide can still contain a mistake or go out of date. If you tell me something on this site is wrong, I will check it against the original source. Then I will either fix the page or explain why it stays as it is. A fixed page gets a new "Last updated" date.
What about links to other websites?
Black Screen Online links to other websites, such as research sources and device makers' help pages, so you can check a fact or follow the maker's own steps. I'm not responsible for what those websites say or do, and their own policies apply.
Does Black Screen Online use advertising or affiliate links?
Where advertising is shown on Black Screen Online, it helps pay for hosting and new tools. Ads never appear inside a full-screen tool or next to its buttons, and no advertiser can pay to change a tool or a guide.
Black Screen Online does not currently use affiliate links or earn commissions from them. If that changes, I will mark affiliate links clearly and explain how they work.
What is Black Screen Online responsible for?
Please use Black Screen Online with your own judgment. The Terms of Use explain the full limits of responsibility, and the Privacy Policy explains how information is handled.
How can you report a problem?
If something on Black Screen Online looks wrong or a tool doesn't work for you, please tell me through the contact page, using "A correction" or "A problem with a tool". You can also email me at ali@blackscreenonline.com.