CodexTheme Tools
Create Theme

Codex Theme Builder · CodexTheme.tools · Free · Local · Unofficial

Build a Codex Desktop theme. Keep it local.

CodexTheme Tools keeps your image in this browser. Tune the interface, compare contrast modes, then export files you can read before placing them yourself. The preview is not an official guarantee.

Open token bench
DarkGraphite Ink · diff surfaces
src/theme.css

Review theme variables.

− --accent: #8A93A1;
+ --accent: var(--theme-accent);
+ --card-opacity: 0.76;
--content-interactive: true;

Readability is measured in the Builder before export.

LightSage Paper · daylight surfaces
src/theme.css

Review theme variables.

− --accent: #8A93A1;
+ --accent: var(--theme-accent);
+ --card-opacity: 0.76;
--content-interactive: true;

Readability is measured in the Builder before export.

High contrastLime Circuit · signal check
src/theme.css

Review theme variables.

− --accent: #8A93A1;
+ --accent: var(--theme-accent);
+ --card-opacity: 0.76;
--content-interactive: true;

Readability is measured in the Builder before export.

  • Runs locally
  • No account
  • Review before use
  • Restore stays visible

Build against the interface, not a moodboard.

Upload, tune, inspect, export. The selected wallpaper stays in this browser.

Live previewMidnight Orbit
Free · Local

Import a codex-theme-v1 color theme in Appearance. No external skin installation is needed.

Live preview
Codex AppTheme v1 handoff

Copy the reviewed import string, then use Settings → Appearance → Import. Nothing is installed or written to your device.

codex-theme-v1:…

Local workspace

What are you working on?

Use in CodexCopy / download data

Native App colors: copy an import string or use the Appearance fields below.

Codex AppTheme v1 import string

Generates a codex-theme-v1: string you paste into the Codex App's own Settings → Appearance → Import dialog. It is separate from the Codex CLI .tmTheme file, from the wallpaper recipe package, and from any external CDP skin.

This is a reviewable user-reported format snapshot checked 2026-08-21, not an official, stable or guaranteed specification. A current or future Codex App may accept it, reject it, or render it differently. Open the Import dialog that matches your light or dark variant, read the payload before importing, and verify the actual app afterwards. Source: openai/codex issue #14766.
Variant
Import into the matching Codex App appearance mode.
Sizes only change this site's preview. The observed Theme v1 payload carries no size field, so they are never written into the string.

Shape matches the reviewed Theme v1 snapshot. Copy and download are enabled.

  1. Copy or download the string. Nothing is sent anywhere and nothing is executed.
  2. Open the Codex App, switch to the matching light or dark appearance, then choose Settings → Appearance → Import.
  3. Read the payload in the dialog, import it, and check Home, a task, a diff and the composer yourself.
  4. If the app rejects or misrenders it, remove it in the same Appearance panel. This site cannot apply, install or restore anything for you.
Codex AppManual Appearance colors

A fallback for builds without an Import dialog: copy these four values and enter them by hand in Codex App's Settings -> Appearance. This site cannot edit the Codex app for you.

Base#080B0D
Accent#B7FF4A
Background#080B0D
Foreground#F5F5F5
  1. Open Codex App and go to Settings -> Appearance.
  2. Paste each value into its matching field: Base, Accent, Background, Foreground.
  3. Review the live preview, then keep or discard. The app stores the choice locally.
Curated · Source checked · Community powered

The community shelf is open.

Like themes globally, save favorites in this browser, and reuse any recipe in the builder. Studio originals fill the shelf while the first community submissions are reviewed.

Explore the community Share a theme
DarkLightMinimalGlassCyberpunkPastel
Studio originals are clearly labeled. Community work will always name its creator, source, and rights status.
We organize and display; creators keep their rights.

Codex Theme does not claim ownership of community submissions or source-linked recommendations. If a listing infringes your rights, contact our copyright desk and we will promptly review and remove or disable valid claims.

Copyright & takedown
Create → Install → Restore

The site exports inputs and instructions. It does not disguise an installer or claim that preview equals compatibility.

Create locally

The public builder keeps your selected image in browser memory and requires no login.

Install transparently

Commands point to the original upstream project and ask for review before execution.

Restore deliberately

Separate prompts keep rollback visible instead of treating it as an afterthought.

Fix a Codex theme when the happy path ends.

If a custom theme breaks after an update, use evidence-based compatibility, troubleshooting, safety, and restore paths instead of downloading an unknown replacement package.

01

Compatibility

Evidence status, platform, architecture, commit, and known limitations.

02

Troubleshooter

Turn a visible symptom into the next safe diagnostic action.

03

Safety

Local image handling, data-only packages, CDP risk, and checksums.

04

Restore

Return to the official appearance before changing more files.

More tools

Free companion pages for other coding agents and Codex plans. No sign-up needed to read them.

01

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Install the open-source Taste Skill and pick one of its 13 skills.

02

OmniRoute Claude Code guide

Run Claude Code through OmniRoute with per-model profiles, locally or on a VPS.

03

OpenCode theme builder

Turn any image into an OpenCode theme in your browser.

04

Codex reset tracker

See when Codex usage limits reset.

05

ChatGPT prices

Compare ChatGPT plan prices by country.

Codex theme questions before export.

Compatibility can change when Codex or the external theme project updates. These answers explain naming, privacy, installation, and the upstream state checked on July 29, 2026.

How are CodexTheme Tools, CodexTheme, and CodexSkin different?

CodexTheme Tools is this independent site; CodexTheme is its shorthand. CodexSkin may refer to other community projects. Choose your export target in the builder: native Codex App colors, Codex CLI syntax, wallpaper data, or a separate external skin workflow. These formats are not interchangeable.

What is a Codex theme?

It depends on the target. A native Codex App theme is a codex-theme-v1 color string imported in Appearance. A CLI .tmTheme file styles code syntax. A wallpaper or recipe is local image or settings data. External skins use a separate community installation workflow, which may use a local browser-debugging connection; native color import does not require that workflow.

Does this modify the official Codex app?

This site exports data and never modifies or launches your apps. Native color themes are applied through the app’s own Appearance settings. External skins have a separate upstream installation and restore path; review that project before running anything.

Is my wallpaper uploaded?

No. The public builder uses your browser’s Object URL and Canvas APIs and never sends the image selected there to the server.

Does it work on macOS?

Choose the target first. Native colors depend on the Appearance options in your installed Codex App; CLI syntax uses /theme. For an external wallpaper skin, the linked upstream macOS studio has its own compatibility and installation instructions. Re-check them before installing.

Does it work on Windows?

Codex Dream Skin v1.3.3 documents an ordinary current-user Setup.exe with a bundled runtime, local image import through the system tray, verification, and restore. It also fixes verification against the wrong fallback theme and hardens slow-start and Store-update recovery. The installer is unsigned, and this site still labels Windows community-tested until we capture our own device evidence.

Can I restore the default Codex appearance?

For native colors, return to a built-in theme in Appearance. For CLI syntax, select another theme with /theme. External skins require their own restore action; the linked v1.3.3 apps expose graphical Restore actions, and the builder provides a reviewable restore prompt.

Is CodexTheme Tools affiliated with OpenAI?

No. CodexTheme Tools is an unofficial community tool and is not affiliated with, endorsed by or sponsored by OpenAI.

Why does a theme sometimes break after an update?

External skins depend on renderer structure that can change when Codex updates. Their compatibility and restore instructions are separate from native Appearance color imports and CLI syntax themes. Check the instructions for your chosen target.

What image size works best?

Use a wide image at least 2000 pixels across, with a calm left side for interface text. The builder exports WebP or PNG at 1920 × 1080 or 2560 × 1440.

Is the builder free?

Yes. Upload, five preview modes, local palette extraction, readability checking, wallpaper, recipe, tokens and data-only ZIP export are free and require no account.