Synthetic intelligence has made large progress in recent times, and considered one of its most fascinating makes use of is in software program growth. Main this modification is OpenAI Codex, a complicated AI system that turns pure language into working code.
Greater than only a helper for programmers, Codex is altering how builders write software program, how individuals who don’t program can work with code, and the way programming itself is altering. This detailed article appears at what OpenAI Codex is, what it may do, the issues it helps remedy, the way it features, and plenty of examples of its use that present its energy to rework.
What’s OpenAI Codex?
OpenAI Codex is a complicated AI mannequin from OpenAI. It comes from the GPT-3 household of fashions however has been specifically educated on billions of traces of publicly obtainable code from GitHub and different locations, in addition to pure language. This particular coaching makes Codex superb at understanding directions in plain human language and creating working code in many alternative programming languages.

OpenAI first launched Codex because the AI behind GitHub Copilot, an “AI pair programmer” that works with well-liked code editors like Visible Studio Code. However its talents go far past simply ending code traces; it’s a versatile device for a lot of coding and software program engineering jobs. As of Might 2025, Codex is being added an increasing number of into platforms like ChatGPT, providing coding assist that’s extra interactive and targeted on duties.
What Does Codex Do? Its Many Skills
Codex’s primary talent is popping pure language directions into code. However it may do way more:
- Pure Language to Code: You possibly can describe a programming job in plain English (or different supported languages), and Codex can create the code for it. This may be making features, entire scripts, or small items of code.
- Code Completion and Ideas: Like GitHub Copilot, Codex can neatly recommend how one can end partly written code, guess what the developer needs to do, and provide helpful code blocks.
- Code Refactoring: Codex can take a look at present code and recommend methods to make it higher, rewrite it to be extra environment friendly, or replace it to make use of newer types or strategies (like altering JavaScript guarantees to async/await).
- Writing Checks: It might probably create unit assessments and different assessments for present features or units of code, serving to to ensure the code is sweet and works reliably.
- Explaining Code: Codex can take a bit of code and clarify what it does in plain language. That is very useful for studying, fixing bugs, or understanding code you haven’t seen earlier than.
- Assist with Debugging: Whereas not an ideal bug-finder, Codex can spot doable bugs in code and recommend fixes primarily based on error messages or the code’s context.
- Knowledge Evaluation and Show: Codex can create code for dealing with information, analyzing it, and making charts or graphs utilizing well-liked instruments like Pandas, NumPy, and Matplotlib in Python.
- Automating Repetitive Jobs: It might probably write scripts to automate widespread growth duties, information entry, file dealing with, and extra.
- Programming {Hardware}: Codex can create code to manage bodily {hardware}, like robots, by understanding high-level instructions and turning them into particular directions for the {hardware}’s software program growth equipment (SDK).
- Translating Code Between Languages: It might probably assist change code from one programming language to a different, although this normally wants a cautious examine by a human.
- Creating SQL Queries: Customers can describe what information they want in plain language, and Codex can write the right SQL queries.
- Making Easy Internet Constructions: It might probably create HTML and CSS for fundamental webpage layouts from descriptions.
What Downside Does Codex Remedy?
Codex helps with a number of large difficulties and challenges in software program growth and different areas:
- Saves Growth Time: By routinely creating widespread code, customary features, and even complicated procedures, Codex makes the event course of a lot quicker.
- Makes Coding Simpler to Begin: Individuals with little or no programming background can use Codex to make easy scripts or perceive code, making it simpler for extra individuals to create with expertise.
- Helps Be taught New Languages and Instruments: Builders can be taught by seeing how Codex turns their plain language descriptions into a brand new language or by asking it to clarify present code.
- Automates Boring Coding Jobs: It frees builders from boring duties, to allow them to concentrate on tougher problem-solving, design, and new concepts.
- Helps Quick Prototyping: Builders can rapidly check out concepts and create working fashions by describing options in plain language.
How Does Codex Work? A Look Inside
Codex’s talents come from the complicated design of huge language fashions (LLMs), significantly the GPT sequence. Right here’s a less complicated concept of the way it works:
- Transformer Design: Like different GPT fashions, Codex makes use of the Transformer neural community design. This design is superb at understanding context and connections in sequence of knowledge, like plain textual content and contours of code.
- Large Coaching Knowledge: Codex was educated on a really giant set of textual content and code. This included a variety of public supply code from locations like GitHub (early variations used about 159 gigabytes of Python code from 54 million sources, and newer fashions use even bigger and extra diverse information) and an enormous quantity of plain textual content.
- Particular Coaching for Code: Whereas it begins with common language understanding (from GPT-3), Codex will get particular coaching for programming duties. This focus helps it perceive programming guidelines, widespread coding methods, how one can use libraries, and the hyperlink between code feedback and the code itself.
- Predictive Creation: When given a immediate (a plain language description or a part of some code), Codex predicts the almost definitely sequence of code “tokens” (the essential elements of code, like key phrases, variables, operators) that ought to come subsequent. It creates code one token at a time, constructing features, statements, and entire applications.
- Understanding Context: A giant energy is its means to recollect and use context from the immediate and any code that got here earlier than it. This lets it create code that is smart with the remainder of this system.
OpenAI is at all times making Codex fashions higher. Newer variations (like these in current ChatGPT updates and the Codex CLI) use extra superior considering talents, such because the “o3” reasoning mannequin talked about in current information.
Successfully speaking your intent to Codex depends closely on crafting clear and exact prompts. To grasp the artwork of instructing AI instruments like Codex for optimum outcomes, think about exploring our Immediate Engineering Course for ChatGPT.
Utilization Examples: Codex in Motion
The easiest way to see what Codex can do is thru examples, lots of that are seen in precise makes use of and discussions:
1. Turning Plain Language into Code (Bouncing Ball Animation)
- Description: A fundamental means is popping a easy concept into working code.
- Utilization Instance: A consumer may ask Codex: “Create a Python script to attract a purple ball bouncing in a Pygame window.” Codex can create:
import pygame
import sys # Good to incorporate for a transparent exit
pygame.init()
screen_width = 800
screen_height = 600
display screen = pygame.show.set_mode((screen_width, screen_height))
pygame.show.set_caption("Bouncing Ball") # Added a window title
# Ball particulars
ball_radius = 10
ball_color = (255, 0, 0) # Purple
ball_rect = pygame.Rect(screen_width // 2 - ball_radius, screen_height // 2 - ball_radius, ball_radius * 2, ball_radius * 2)
dx, dy = 5, 5 # Pace and path
clock = pygame.time.Clock() # For controlling velocity
whereas True:
for occasion in pygame.occasion.get():
if occasion.sort == pygame.QUIT:
pygame.stop()
sys.exit()
ball_rect.x += dx
ball_rect.y += dy
# Test for hitting partitions
if ball_rect.left <= 0 or ball_rect.proper >= screen_width:
dx = -dx
if ball_rect.prime <= 0 or ball_rect.backside >= screen_height:
dy = -dy
display screen.fill((0, 0, 0)) # Black background
pygame.draw.circle(display screen, ball_color, ball_rect.middle, ball_radius)
pygame.show.flip()
clock.tick(60) # Maintain it at 60 frames per second
2. Utilizing Codex CLI for Terminal-Primarily based Coding (Refactoring)
- Description: The OpenAI Codex CLI lets builders use Codex of their terminal for jobs like enhancing code, writing assessments, or creating code proper of their ordinary work setup.
- Utilization Instance: A developer of their terminal:
codex --model o4-mini "Enhance the operate 'fetchData' in 'utils.ts' to make use of async/await and higher error dealing with."
If utils.ts had:
// utils.ts
operate fetchData(id: string) {
return fetch(`https://api.instance.com/information/${id}`)
.then(res => {
if (!res.okay) {
throw new Error(`HTTP error! standing: ${res.standing}`);
}
return res.json();
});
}
Codex can recommend:
// utils.ts (improved by Codex)
async operate fetchData(id: string) {
strive {
const res = await fetch(`https://api.instance.com/information/${id}`);
if (!res.okay) {
throw new Error(`HTTP error! standing: ${res.standing}`);
}
return await res.json();
} catch (error) {
console.error("Didn't fetch information:", error);
throw error; // Move the error to the half that known as this operate
}
}
The CLI would present the adjustments for overview, and the developer may settle for them.
3. Automating Jobs with Codex in ChatGPT (Bug Fixing)

Description: When a part of ChatGPT, Codex can act like a “digital staff member,” doing software program engineering work like including options, fixing bugs, and creating pull requests in a protected, separate setting.
Utilization Instance: A developer connects Codex in ChatGPT to a GitHub undertaking and asks: “Repair the bug in payment_processing.py the place reductions for ‘PREMIUM’ customers don’t work if their cart whole is beneath $50.” Codex would:
- Copy the undertaking into its protected setting.
- Have a look at payment_processing.py to search out the low cost guidelines.
- Discover the wrong situation.
- Recommend a repair, perhaps by altering a situation or including a brand new one.
- Write or replace assessments for this particular case.
- Run assessments to examine the repair.
- Create a pull request with the code adjustments, take a look at outcomes, and a abstract of the repair for the developer to look over.
4. Programming a Robotic with Codex
Description: Codex can flip high-level directions into working code for complicated {hardware}, like programming robots.
Utilization Instance: A developer asks Codex: “Write a Python script utilizing the Unitree SDK to make the A1 robotic arise, stroll ahead 0.5 meters slowly, after which sit down.” Codex can create (a simplified concept):
from unitree_legged_sdk import HighCmd, HighState, LowCmd, LowState, MotorCmd, MotorState, LeggedMSG # Assuming right SDK elements
# Arrange connection and robotic state data
robotic = # ... (SDK-specific setup) ...
strive:
robotic.join() # Or the suitable connection methodology
print("Robotic standing up...")
robotic.stand_up() # Concept of an SDK operate
robotic.wait_for_motion_complete()
print("Robotic strolling ahead...")
robotic.move_forward(distance=0.5, velocity=0.2) # Concept of an SDK operate
robotic.wait_for_motion_complete()
print("Robotic sitting down...")
robotic.sit_down() # Concept of an SDK operate
robotic.wait_for_motion_complete()
besides Exception as e:
print(f"An error occurred: {e}")
lastly:
print("Disconnecting robotic.")
robotic.disconnect()
5. Modifying Codex CLI for Customized Fashions
That is wild. In only a few hours my good friend forked Open AI Codex to work with Gemini 2.5 Professional 🤯 pic.twitter.com/gENT01q82P
— Sawyer Hood (@sawyerhood) April 17, 2025
- Description: As a result of instruments just like the Codex CLI are open-source, builders can change them to work with different AI fashions, making them extra versatile.
- Utilization Instance: A developer utilizing a modified Codex CLI with Gemini 2.5 Professional can sort:
codex-gemini "Create a Node.js script that units up an Specific server with one GET endpoint '/standing' that returns { standing: 'okay' } as JSON."
The modified CLI, working with Gemini, can produce:
const specific = require('specific');
const app = specific();
const port = 3000;
app.get('/standing', (req, res) => {
res.json({ standing: 'okay' });
});
app.pay attention(port, () => {
console.log(`Server listening at http://localhost:${port}`);
});
6. Creating SQL Queries
- Description: Codex could make database work simpler by turning plain language requests into SQL.
- Utilization Instance: Immediate: “Write an SQL question to search out the names and e-mail addresses of all clients from the ‘Clients’ desk who dwell in ‘California’ and have ordered one thing within the final 30 days. Get this by becoming a member of with the ‘Orders’ desk on ‘CustomerID’.” Codex may create:
SELECT c.CustomerName, c.E mail
FROM Clients c
JOIN Orders o ON c.CustomerID = o.CustomerID
WHERE c.State="California"
AND o.OrderDate >= DATE('now', '-30 days');
Learn: How one can prepare Codex on a posh SQL legacy database mannequin
7. Writing Unit Checks
- Description: Ensuring code is sweet high quality by computerized testing.
- Utilization Instance: Given a Python operate:
def calculate_discount(worth, proportion):
if not 0 <= proportion <= 100:
elevate ValueError("Low cost proportion have to be between 0 and 100.")
return worth * (proportion / 100.0)
Immediate: “Write pytest unit assessments for the Python operate calculate_discount.”
Codex can create:
import pytest
from your_module import calculate_discount # Assuming the operate is in your_module.py
def test_calculate_discount_valid():
assert calculate_discount(100, 10) == 10.0
assert calculate_discount(200, 25) == 50.0
assert calculate_discount(75, 0) == 0.0
assert calculate_discount(50, 100) == 50.0
def test_calculate_discount_invalid_percentage():
with pytest.raises(ValueError, match="Low cost proportion have to be between 0 and 100."):
calculate_discount(100, -10)
with pytest.raises(ValueError, match="Low cost proportion have to be between 0 and 100."):
calculate_discount(100, 110)
def test_calculate_discount_edge_cases():
assert calculate_discount(0, 50) == 0.0
assert calculate_discount(123.45, 10) == 12.345
Codex in Completely different Environments
OpenAI Codex expertise might be accessed in a number of methods:
- OpenAI API: Builders can add Codex talents proper into their very own apps, merchandise, and work processes utilizing the OpenAI API. This lets them make customized options for particular wants.
- GitHub Copilot: That is possible essentially the most well-known use of Codex. GitHub Copilot works as an AI pair programmer inside code editors, providing real-time code options and completions.
- ChatGPT Integration: As proven within the X examples, Codex is being put extra deeply into ChatGPT. This lets customers give complicated coding jobs, ask questions on code, and handle software program tasks in a chat-like manner. These setups usually have protected, separate areas for working and testing code.
- Codex CLI: The command-line device lets builders who like working in a terminal use Codex for code creation, evaluation, and adjustments proper of their native growth setups.
- Codex and Microsoft Phrase (and different Workplace Apps): Whereas there is probably not a separate “Codex plugin for Microsoft Phrase,” OpenAI’s expertise (like what runs Codex) is an enormous a part of Microsoft’s Copilot for Microsoft 365. Customers can use AI to:
- Create textual content and content material: Write drafts of paperwork, emails, or displays.
- Summarize lengthy paperwork: Shortly get the details of textual content.
- Rewrite or rephrase textual content: Make textual content clearer or change its tone.
- Automate jobs: One instance confirmed Codex creating code to inform Microsoft Phrase to do issues like take away all further areas from a doc. Whereas instantly creating code inside Phrase for Phrase’s personal scripting (like VBA) with Codex is much less widespread, the essential pure language understanding and textual content creation are very helpful. Builders also can make Workplace Add-ins that use the OpenAI API to convey Codex-like options into Phrase.
Knowledge Science with OpenAI Codex
Codex is turning into a really useful device for information scientists:
- Sooner Scripting: Knowledge scientists can describe information cleansing steps, statistical checks, or how they need charts to look in plain language, and Codex can create the Python (with Pandas, NumPy, SciPy, Matplotlib, Seaborn), R, or SQL code.
- Instance Immediate: “Write Python code utilizing Pandas to load ‘sales_data.csv’, discover the full gross sales for every product sort, after which make a bar chart of the outcomes utilizing Matplotlib.”
- Easier Advanced Queries: Creating difficult SQL queries for getting and arranging information turns into simpler.
- Exploratory Knowledge Evaluation (EDA): Codex can rapidly create small bits of code for widespread EDA jobs like checking for lacking data, getting fundamental statistics, or making first-look charts.
- Studying New Libraries: Knowledge scientists can discover ways to use new libraries by asking Codex to create instance code for sure jobs.
- Automating Report Creation: Scripts to get information, do analyses, and put outcomes into experiences might be drafted with Codex’s assist.
Codex is turning into a really useful device for information scientists, able to aiding with many duties. If you happen to’re trying to construct a powerful basis or advance your expertise in leveraging AI for information evaluation, our complete e-Postgraduate Diploma in Synthetic Intelligence and Knowledge Science by IIT Bombay can offer you in-depth coaching.
Advantages of Utilizing Codex
- Extra Productiveness: Significantly cuts down time spent on writing customary and repetitive code.
- Higher Studying: Acts as an interactive solution to be taught programming languages, libraries, and concepts.
- Simpler Entry: Makes coding much less intimidating for newcomers and non-programmers.
- Fast Prototyping: Permits quick creation of working fashions from concepts.
- Give attention to Larger Issues: Lets builders think about construction, logic, and consumer expertise as a substitute of routine coding.
- Consistency: May also help maintain coding model and requirements if guided appropriately.
Limitations and Issues to Suppose About
Even with its energy, Codex has some limits:
- Accuracy and Correctness: Code from Codex isn’t at all times good. It might probably make code that has small errors, isn’t environment friendly, or doesn’t fairly do what the immediate requested. At all times examine code made by Codex.
- Understanding Advanced or Unclear Prompts: Codex may need bother with prompts which have many steps, are very complicated, or are worded unclearly. It generally makes code that isn’t the most effective or is mistaken. It really works finest for clearly outlined jobs.
- Outdated Info: The mannequin’s data relies on its coaching information, which has a deadline. It may not know concerning the very latest libraries, API adjustments, or safety points discovered after its final coaching.
- Safety Points: Codex may by accident create code with safety weaknesses if these kinds_of patterns have been in its coaching information. Cautious safety checks are wanted for any code utilized in actual merchandise.
- Bias: Like all AI fashions educated on giant web datasets, Codex can present biases from that information. This might result in unfair or skewed ends in some conditions.
- Over-Reliance: New programmers may rely an excessive amount of on Codex with out totally understanding the code. This might decelerate their studying.
- Context Window: Whereas getting higher, LLMs can solely bear in mind a specific amount of data. They may lose monitor of earlier elements of a really lengthy dialog or piece of code.
- Moral Factors: Questions on who owns the rights to generated code (because it’s educated on present code), lack of jobs, and doable misuse for creating dangerous code are nonetheless being mentioned within the AI world.
- Security Throughout Working (The way it’s Dealt with): As talked about, newer methods of utilizing Codex (like in ChatGPT and the Codex CLI) usually run in a protected, separate space with no web entry whereas a job is working. This limits what it may do to the code offered and already put in instruments, making it safer.
Availability
As of early 2025:
- Codex options are an enormous a part of GitHub Copilot.
- Superior Codex options are supplied to ChatGPT Professional, Enterprise, and Workforce subscribers, with plans to supply them to Plus and Edu customers later.
- The OpenAI Codex CLI is open-source and can be utilized with an OpenAI API key.
- Direct entry to Codex fashions can also be doable by the OpenAI API for builders to make their very own purposes.
The Way forward for Codex and AI in Coding
OpenAI Codex and related AI applied sciences are set to essentially change software program growth. We are able to anticipate:
- Smarter AI Coding Helpers: AI will get even higher at understanding what customers need, dealing with complicated duties, and dealing with builders.
- Higher Integration with Code Editors and Workflows: AI instruments will match easily into all elements of the event course of.
- AI-Helped Software program Design: AI may assist with larger design selections and planning the construction of software program.
- Computerized Bug Fixing and Maintenance: AI may tackle a bigger position to find, understanding, and even fixing bugs in dwell techniques.
- Progress of Low-Code/No-Code: AI like Codex will give extra energy to “citizen builders” (individuals who aren’t skilled programmers however construct apps) and velocity up what low-code/no-code platforms can do.
- Adjustments in Developer Jobs: Builders will possible spend extra time defining issues, designing techniques, guiding AI, and checking AI-made code, fairly than writing each line by hand.
OpenAI sees a future the place builders give routine jobs to AI brokers like Codex. This could allow them to concentrate on larger plans whereas being extra productive. This implies working with AI in real-time, deeper connections with developer instruments (like GitHub, difficulty trackers, and CI techniques), and mixing dwell AI assist with assigning jobs that may be finished later.