How to turn on dark mode on X (Dim or Lights out)
X ships two dark themes, Dim and Lights out, and sets them separately on web, iPhone and Android. Here are the exact paths and what the setting never touches.
The short version
- ▸X has two dark themes, not one: Dim (dark blue-grey) and Lights out (true black). Both live in the same Display screen.
- ▸The paths differ per surface. Web: More, then Display. iOS: Settings and privacy, then Accessibility, display, and languages, then Display and sound. Android: the same menu, then Display, then Dark mode.
- ▸The fast route on mobile is the light bulb icon in your profile menu, and on an iPad keyboard X lists cmd-M.
- ▸Only the Android app documents a Use device settings option that follows your phone's theme. The x.com dialog is a fixed choice between white, Dim and Lights Out.
- ▸Dark mode changes X's interface, not the media in posts. White screenshots and transparent-background logos still glow, which matters for anyone posting images.
Quick answer
To turn on dark mode on X (formerly Twitter): on x.com click More, then Display, then choose Dim or Lights Out. In the iPhone app go to Settings and privacy, then Accessibility, display, and languages, then Display and sound, then flip the Dark mode slider. On Android the same menu leads to Display, then Dark mode. There are two dark themes, and you set them separately on every device you sign in from.
Both of those details trip people up. Searchers expect one switch for the account, find it does not travel with them, and assume something broke.
Last updated: September 2026
Turn it on, per surface
The paths below come from X's own help pages, which document each platform separately.
On x.com in a browser. Click More in the left menu, then Display. X's new user FAQ describes the dialog: pick your font size and colour, then "use the radio buttons to choose between the default white background or the two dark mode options Dim and Lights Out." Everything in that panel previews live, so you can see the change before you commit to it.
On iPhone and iPad. From your profile menu, tap Settings and privacy, then Accessibility, display, and languages, then the Display and sound tab. Drag the font slider if you want bigger text, tap the Dark mode slider to turn the theme on, then choose Dim or Lights out. Tapping the slider again puts you back on white (X for iOS help).
On Android. Tap your profile icon, then Settings and privacy, then Accessibility, display and languages, then Display, then Dark mode (X for Android help).
The shortcut worth remembering. In both mobile apps, open your profile menu and tap the light bulb icon. It drops you straight into the dark mode controls with no menu diving. And if you use X on an iPad with a keyboard attached, X lists cmd-M as enable or disable dark mode, alongside cmd-plus and cmd-minus for text size.
Dim or Lights out: they are not the same thing
Two themes, one obvious difference and one that only shows up on certain hardware.
| Theme | Background | Best for |
|---|---|---|
| Dim | Dark blue-grey | Daytime and mixed lighting, softer contrast against surrounding light |
| Lights out | True black | Night use, OLED phone screens, maximum contrast |
On an OLED panel, a true black pixel is an unlit pixel. Lights out therefore looks deeper than Dim and draws less from the battery on that hardware, which is the practical reason to pick it on a modern phone. On an LCD laptop screen the backlight stays on regardless, so the choice there is purely about which one your eyes prefer after an hour.
X's accessibility features list confirms dark and dim modes ship on web, iOS and Android alike, so you are not choosing between platforms, only between looks.
Why it did not carry over to your other device
This is the complaint behind most "X dark mode not working" searches. You set Lights out on your phone at midnight, open the laptop the next morning, and get a wall of white.
Nothing reverted. X documents the theme as a per-surface display setting with its own path on x.com, iOS and Android, so each place you sign in keeps its own answer. A second browser, or even a fresh profile in the same browser, counts as a new surface and starts on the default. If x.com in a browser is your main home for X, the rest of what the web app does differently is mapped in how to use X in a web browser.
Android has the one automation escape hatch. X's help page describes a Use device settings option, which hands the decision to your phone. If Android is already scheduled to flip to dark at sunset, X follows along. X does not document an equivalent auto option for x.com, where the radio buttons are a fixed choice, so browser extensions that force dark themes onto websites are the only route there and they repaint pages without knowing what X intended.
If your phone theme is inconsistent because you use X across an app and a browser on the same device, how to get the X app covers which surfaces you actually have signed in.
What dark mode does not touch
Media inside posts. The theme repaints X's own interface. It has no say over the images and video people upload. A screenshot with a white background, a chart exported from a spreadsheet, or a logo saved as a transparent PNG will all glow against a dark timeline. If you post images, that is a reason to check how your media reads on both backgrounds before publishing, and the dimensions that stop X cropping your work badly are in X image sizes.
Embedded posts on other sites. An X post embedded in an article is rendered by that website, using whichever theme the site author chose when they generated the embed code. Your account setting does not reach it. The theme options available when you generate that code are part of how to embed a post on X.
What anyone else sees. Themes are viewer-side. Your dark timeline is invisible to your followers, who each see X in whatever they picked.
The rest of the Display screen
While you are in there, the same panel carries the other visual controls, and they are worth two minutes.
Font size is a slider on both the web dialog and the iOS Display and sound tab. On Android, X's accessibility documentation points to font size customisation as well.
Text colour on x.com changes the accent colour used for links, buttons and the post composer. It is cosmetic, but a high-contrast accent against Lights out is noticeably easier to scan than the default blue on black.
High contrast mode appears in X's accessibility list for web and iOS, and it is the setting to reach for if Dim still feels washed out rather than merely dark.
One screen up, under the same Accessibility, display, and languages menu, sits Data usage and the video controls. If motion bothers you as much as brightness does, how to turn off autoplay on X covers that half of the problem.
If the option is missing or stuck
A few quick checks before assuming a bug.
Look in the right menu. Dark mode is under Display, not under Privacy and safety or Notifications, and X moves menu labels around between app versions. If your app shows fewer options than X's help pages describe, you are on an older build, and the app store update usually restores them.
On desktop, remember that your operating system's dark theme does not drive x.com. macOS or Windows set to dark will darken your browser chrome and leave the X timeline white until you set it inside X. That mismatch is normally what people are seeing when they say the setting will not stick.
Bottom line
More, then Display on the web. Settings and privacy, then Accessibility, display, and languages on mobile, or the light bulb icon in your profile menu if you want it in two taps. Pick Dim for daytime and Lights out for night or an OLED screen. Then repeat it on every device and browser you use, because X keeps the theme per surface rather than per account.
And if dark mode is on your list because you are on X late and often, the lever that matters is not the palette, it is how much of the posting you do by hand. X-Autopilot drafts and posts from your own logged-in browser on your Mac, so your session cookie never leaves the machine. That is a smaller detection surface than a cloud tool posting from a shared IP pool, though no browser-based automation is sanctioned by X's rules.
Frequently asked
Answers indexed by Google + AI assistants.
How do I turn on dark mode on X?+
On x.com, click More, then Display, then pick Dim or Lights Out with the radio buttons. On iPhone, go to Settings and privacy, then Accessibility, display, and languages, then Display and sound, then the Dark mode slider. On Android, the path is Settings and privacy, then Accessibility, display and languages, then Display, then Dark mode.
What is the difference between Dim and Lights out?+
Both are dark themes. Dim uses a dark blue-grey background, Lights out uses true black. On an OLED phone screen, true black means those pixels are switched off rather than lit dark, which is why Lights out looks deeper and is the one battery-conscious users pick.
Why is my X dark mode on my phone but not on my laptop?+
Because the theme is set where you use X, not once for the account. X publishes a separate Display path for x.com, iOS and Android, so signing in somewhere new starts you back on the default white background. A fresh browser or browser profile counts as somewhere new.
Can X follow my phone's system dark mode automatically?+
On Android, yes. X's help page describes a Use device settings option, which is useful if you already have your phone scheduled to switch themes at sunset. X does not document an equivalent auto option in the x.com Display dialog, which offers fixed background choices.
Is there a faster way than the settings menu?+
Yes. In the mobile apps, open your profile menu and tap the light bulb icon, which jumps straight to the dark mode controls. On an iPad with a connected keyboard, X lists cmd-M as the shortcut to enable or disable dark mode.
Why do some posts still look bright in dark mode?+
The theme repaints X's interface, not the media inside posts. Images, video thumbnails and screenshots keep their own backgrounds, so a white screenshot or a logo saved as a transparent PNG will glow against a dark timeline. That is a content problem, not a settings one.
- X Help - New user FAQ: the x.com path (More, then Display) with font size, text colour and the white / Dim / Lights Out radio buttons (Wayback capture 7 September 2026)
- X Help - How to use X for Android: the Settings and privacy to Display to Dark mode path, the light bulb shortcut, the Use device settings option and the Dim / Lights out themes (Wayback capture 14 February 2026)
- X Help - How to use X for iOS and iPhone: the Display and sound tab, the Dark mode slider, the font slider and the cmd-M keyboard shortcut (Wayback capture 19 May 2026)
- X Help - Accessibility features of X: the per-platform list confirming dark and dim modes plus font size customisation on web, iOS and Android (Wayback capture 3 September 2026)
Product designer and indie hacker. Runs the agent on his own X account every day and writes up what the data shows, including when it's inconvenient.
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