Codex vs Claude Code: Which Coding Agent Should You Choose?

If you have been following AI tools this year, you have probably heard two names come up whenever people talk about coding agents: OpenAI Codex and Claude Code. Many office workers and small-business owners assume both tools are strictly for software engineers. In reality, anyone can use them to inspect files, clean up spreadsheets, and build simple web pages directly inside a folder on their own computer — using plain English or Bahasa Melayu instructions.

Here is what each tool actually is:

OpenAI Codex is OpenAI's agent dedicated to software development and technical work. It is now built right into the ChatGPT desktop app (and is also available on the web, in the terminal / CLI, as an IDE extension, and on iOS depending on your plan). When you pick a folder on your computer, Codex can read and modify files in that folder after you approve its actions.

Claude Code is Anthropic's coding agent that runs in a terminal or inside the Code tab of the Claude desktop app. Just like Codex, it reads and edits files inside a local folder you choose and asks for your permission before modifying files or running commands.

Comparison table: OpenAI Codex vs Claude Code (Checked 7 Nov 2026)

Based on OpenAI and Anthropic's official documentation and Malaysian subscription pricing checked in November 2026, here is how the two compare side by side:

Item	Codex	Claude Code
Cheapest way in	Free or Go in the ChatGPT desktop app (rolling out)	Needs Claude Pro or higher; the free plan has no Claude Code
Price per month (Nov 2026)	Go RM24, Plus RM99.90, Pro from RM420	Pro USD 20 (USD 17 billed yearly), Max USD 100, Ultra USD 200, excluding tax
Without a terminal	ChatGPT desktop app, choose Codex	Claude desktop app, Code tab
With a terminal	One install command (below)	One install command (see the Claude Code guide)
Where it runs	Desktop; Plus and up also on web, terminal, code editors and iOS	Desktop (Windows, Mac) and terminal

In ChatGPT, ChatGPT Work and Codex share the same usage allowance. In Claude, regular claude.ai web chats and Claude Code draw from the same shared usage pool. Both tools have usage limits that vary with task complexity — check your account's usage dashboard for your remaining allowance.

Getting started with OpenAI Codex

You can start using Codex either through the graphical desktop app (the easiest option for beginners) or through your computer's terminal (CLI).

Option 1: Use the ChatGPT desktop app (No terminal required)

According to OpenAI's official quickstart guide, the simplest way to use Codex is inside the ChatGPT desktop app:

Download and install the ChatGPT desktop app (available for Windows, macOS, and Linux), open the app, and sign in with your ChatGPT account.
- You should see: The main ChatGPT desktop app window on your screen.
Click the ChatGPT dropdown menu and select Codex.
- You should see: The Codex workspace open with an option to pick a local folder on your computer.
To pick a folder, click the folder button above the message box, choose New project, give it a name, click Add and select your folder, then click Create project.
- You should see: Codex asks Trust this folder? and warns that it can read, edit and run files there. Click Trust folder only for your own test folder. The screen then says What should we work on in (your project name).

Option 2: Install Codex in the Terminal (CLI) on Windows or Mac

If you are on ChatGPT Plus (or higher) and want to run Codex directly inside a terminal window on Windows 10, Windows 11, or Mac:

Run the exact official install command for your operating system:
- On Windows: Open a new PowerShell window (Start these from a new PowerShell window), paste the exact command below, and press Enter:

powershell -ExecutionPolicy ByPass -c "irm https://chatgpt.com/codex/install.ps1 | iex"

- **On macOS or Linux:** Open **Terminal**, paste the exact command below, and press Enter:

curl -fsSL https://chatgpt.com/codex/install.sh | sh

- **You should see:** The installer finish downloading and setting up the Codex CLI. *(Note: Running the exact same install command above also updates Codex when a newer version comes out).*

Open a terminal window inside your project folder, type the command below, and press Enter:

codex

- **You should see:** On your first run, Codex asks you to sign in. Choose **Sign in with ChatGPT** and complete the login in your browser.

Once signed in, you can type instructions in plain language or use these five official slash commands inside the Codex CLI:
- /init — creates an AGENTS.md instructions file for your project folder;
- /status — shows your current session settings and remaining limits;
- /permissions — chooses what Codex is allowed to do;
- /model — picks the AI model; and
- /review — reviews changes made to your files.

Getting started with Claude Code

Just like Codex, Claude Code gives you two ways in: a no-terminal route via the Code tab inside the Claude desktop app (claude.com/download), or a terminal route by installing the CLI and running claude.

Because I already wrote a complete step-by-step installation walkthrough for Windows and Mac in Week 1, read Claude Code: Complete Beginner Guide for Windows & Mac for the full setup commands and troubleshooting tips.

One real first task in both tools: Turn a CSV into a printable price-list page

The best way to compare Codex and Claude Code is to give both tools the exact same practical task: reading a small product spreadsheet (produk.csv) and generating a clean, printable price-list web page (senarai-harga.html) that you can open in any browser.

Step 1: Create a COPY folder (`Price-Test`) and `produk.csv`

On your computer's Desktop (Windows 10, Windows 11, or Mac), create a new folder named Price-Test.
- You should see: An empty Price-Test folder on your Desktop.
Open Notepad (on Windows) or TextEdit in plain-text mode (on Mac), copy the exact CSV content below, and save it inside Price-Test as produk.csv:

Menu,Kategori,Saiz,Harga_RM,Catatan
Nasi Lemak Ayam Berempah,Makanan Utama,1 Set,12.50,Termasuk sambal dan telur rebus
Mee Goreng Mamak,Makanan Utama,1 Pinggan,9.00,Boleh pilih tahap pedas
Karipap Pusing Kentang,Kuih Petang,3 Biji,4.50,Digoreng panas setiap petang
Teh Tarik Kaw,Minuman,1 Cawan,3.50,Panas atau ais tambah RM0.50
Kopi O Kampung,Minuman,1 Cawan,3.00,Biji kopi tempatan

- **You should see:** The file `produk.csv` saved inside your `Price-Test` folder.

Step 2: Open `Price-Test` in Codex or Claude Code

Open your chosen agent — either Codex (in the ChatGPT desktop app or via codex in your terminal) or Claude Code (in the Claude desktop app's Code tab or via claude in your terminal) — and select the Price-Test folder.
- You should see: The agent workspace active inside the Price-Test folder.

Step 3: Run the price-list page prompt

Copy and paste the exact prompt below (it works identically in both Codex and Claude Code):

Read the file produk.csv in this folder. Do not modify or delete produk.csv.

Using the data inside produk.csv, create a new single-page HTML file named senarai-harga.html that displays a clean, mobile-friendly shop price list formatted for A4 printing.

Group the items by category (Makanan Utama, Kuih Petang, Minuman), show every price in RM with two decimal places, and include a "Cetak Senarai Harga" button at the top that triggers the browser print dialog.

- **You should see:** I tested this prompt in both tools on 7 Nov 2026. **Claude Code** finished in about 1 minute 20 seconds. **Codex** wrote a one-line plan first, then finished in about 3 minutes 20 seconds, with an **Open in** button to open the page and an **Undo** button if you want to reverse the change. Both created **`senarai-harga.html`** and left `produk.csv` untouched. Depending on your permission settings, the agent may ask first or simply get on with it.

Step 4: Open `senarai-harga.html` in your browser

Double-click senarai-harga.html inside your Price-Test folder to open it in Chrome, Edge, or Safari.
- You should see: A clean, printable price-list page grouped by category with all five items, RM prices, and a working print button at the top.

Which one should you choose?

Both agents handle everyday file tasks and HTML page building reliably. Here is a practical rule of thumb so you don't pay for two subscriptions unnecessarily:

If you already pay for ChatGPT Plus (RM99.90/month): Start with OpenAI Codex. Your Plus plan already includes Codex across the desktop app, web, terminal (CLI), IDE extension, and iOS.
If you already pay for Claude Pro (USD 20/month monthly or USD 17/month annual): Start with Claude Code in the Claude desktop app or terminal.
If you are on a free plan (RM0): Download the ChatGPT desktop app and check if Codex is available on your account (OpenAI includes Codex on Free and Go in the desktop app, subject to rollout). Claude's free plan does not include Claude Code.

3 essential safety rules

Whenever you use Codex or Claude Code on your computer, follow these three safety rules:

3 Safety Rules for Coding Agents:

Always work on a COPY of your folder: Beginners should always duplicate a folder before running tasks so original files stay untouched. (If you use Git, OpenAI's official Codex docs recommend creating Git checkpoints before and after a task so you can revert changes easily).
Read every approval request before accepting: Always review what the agent wants to edit or run before approving. In the Codex CLI, you can also inspect or adjust permissions using /permissions.
Never paste passwords or API keys: Never put banking passwords, IC numbers, or secret API keys into the prompt box or inside a folder connected to an agent.

What's next?

Now that you have generated your first HTML page on your computer, see how to build a complete one-page business website preview in my companion guide: How to Build a Business Website with AI in Malaysia.

Step-by-step Bina dengan AI (Build with AI) recipes are coming soon (akan datang). In the meantime, explore more free guides on the Belajar AI hub or start with the 4 free Mula Sini starter recipes.