Create Custom Themes
for Codex

Choose a preset, customize every color, and install it in Codex in minutes.
No coding or config editing required.

Create Your Theme Browse presets

Free · No sign-up · Works offline

CodexTheme Workspace — Afterglow
YOUR PERSONAL WORKSPACE Afterglow

A calmer place to ship ambitious work.

Build a landing page ↗ Review my code ↗
Ask CodexTheme to build something… ↑

From artwork to theme
in three steps.

Choose your platform at the end and follow a guided install flow for Codex App or Codex CLI.

STEP 01

Drop in your artwork

Drag any PNG, JPG, or WebP into the editor — or start from one of twenty curated presets. Your image never leaves the browser.

Drop an image hereor click to browse · max 16 MB
STEP 02

Tune the mood

Tune the installable accent, background, foreground, and CLI syntax colors. Artwork and effects help you shape the mood in the live preview.

STEP 03

Install in Codex

Copy exact Appearance values for Codex App, or download a real .tmTheme file for Codex CLI.

◈ Codex App⌘ .tmTheme/theme

Start from a preset.
Make it yours.

Twenty moods, already orchestrated. Pick one and keep tuning — it opens right in the Studio.

Local-first.
Private by default.

CodexTheme Studio is a browser app, not a service. Your artwork and settings stay on your device — the editor even works offline once installed.

  • ⌂
    Local-first by designArtwork and theme content are not uploaded to CodexTheme; hosting and font requests may create limited technical logs.
  • ▤
    Saved on your deviceA local theme library keeps up to eight of your favorite builds.
  • ⬇
    Installable PWAAdd it to your dock or home screen and keep designing offline.
  • ◐
    Dark, light & auto modesPreview your theme against the mode your workspace actually uses.

One theme.
Two real install paths.

CodexTheme matches the official capabilities of Codex App and Codex CLI instead of giving you generic files that cannot be installed.

No terminal ◈

Codex App

Copy your base theme, accent, background, and foreground values, then apply them in Settings → Appearance.

Installable file ⌘

Codex CLI

Download a valid .tmTheme file, copy it into $CODEX_HOME/themes, and select it with /theme.

✓

Guided steps

Every result includes platform-specific instructions, commands, and clear notes about what Codex supports.

🔒

Local generation

Your theme and artwork stay in the browser while all install files and values are generated locally.

Questions, answered.

Does my artwork get uploaded anywhere?

No. Uploaded artwork and theme content are processed locally in your browser and are not uploaded to CodexTheme. Standard hosting and Google Fonts requests may still generate limited technical logs, such as IP address, browser details, requested pages, and timestamps.

Which Codex products are supported?

CodexTheme follows the supported Codex paths. For Codex App, copy the generated values into Settings → Appearance. For Codex CLI, download the .tmTheme file, place it in $CODEX_HOME/themes, and select it with /theme.

Is CodexTheme Studio free?

Yes — completely. No seats, no tiers, no sign-up. Open the Studio and start designing.

Does it work offline?

Yes. CodexTheme Studio is an installable PWA with an offline cache, so the editor and your saved themes keep working without a connection.

Ready to make something
wonderful?

Create Your Theme

Free to create and preview · No account · Your artwork stays yours