Add to ChromeHow to change the Claude theme
Updated
Short answer
On claude.ai, click your initials in the lower left, open Settings → Appearance, and choose Color mode: Light, Match System or Dark. The same page has Chat font (Default, Match System, Dyslexic Friendly). Claude has no accent colours, backgrounds or custom themes built in; for those, use an extension such as ChatTheme.
Turn on Claude dark mode
This guide is about Claude in the browser (claude.ai). Claude Code, the command-line tool, has its own /theme command.
- 1
Open Settings
On claude.ai, click your initials or name in the lower-left corner and choose Settings.
- 2
Go to Appearance
Open the Appearance section.
- 3
Pick a color mode
Choose Light, Match System (follows your computer) or Dark.
Change the chat font
Settings → Appearance also has Chat font with three options: Default, Match System and Dyslexic Friendly. There is no font size setting; use browser zoom (Ctrl or Cmd with + and −).
Custom themes for Claude
Claude has no accent colour, background or theme options beyond light and dark. ChatTheme adds them: pick a built-in look like Classic Mac, Windows 95 or Paper, or describe one and AI designs it. Every Claude feature keeps working, and Alt+Shift+T turns themes off instantly.
- 1
Install ChatTheme
Add ChatTheme from the Chrome Web Store (Chrome, Edge, Brave, Arc).
- 2
Open the side panel on claude.ai
Click the ChatTheme icon in the toolbar.
- 3
Pick or create a theme
Click a theme, or describe one in the Create tab. The same theme also applies on chatgpt.com.
Try ChatTheme
Free for ChatGPT, Claude and Gemini. Only the look changes.