Synthetic intelligence has made large progress lately, and one in all its most attention-grabbing makes use of is in software program improvement. 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 could possibly do, the issues it helps remedy, the way it features, and plenty of examples of its use that present its energy to remodel.
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 skilled on billions of strains of publicly out there code from GitHub and different locations, in addition to pure language. This particular coaching makes Codex excellent 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 fashionable code editors like Visible Studio Code. However its talents go far past simply ending code strains; it’s a versatile instrument 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 centered on duties.
What Does Codex Do? Its Many Skills
Codex’s essential ability is popping pure language directions into code. However it could possibly do rather more:
- Pure Language to Code: You may describe a programming job in plain English (or different supported languages), and Codex can create the code for it. This may be making features, complete scripts, or small items of code.
- Code Completion and Options: Like GitHub Copilot, Codex can neatly counsel tips on how to end partly written code, guess what the developer desires to do, and supply helpful code blocks.
- Code Refactoring: Codex can take a look at current code and counsel methods to make it higher, rewrite it to be extra environment friendly, or replace it to make use of newer kinds or strategies (like altering JavaScript guarantees to async/await).
- Writing Assessments: It could actually create unit exams and different exams for current features or units of code, serving to to verify the code is nice and works reliably.
- Explaining Code: Codex can take a chunk 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 counsel fixes based mostly on error messages or the code’s context.
- Information Evaluation and Show: Codex can create code for dealing with knowledge, analyzing it, and making charts or graphs utilizing fashionable instruments like Pandas, NumPy, and Matplotlib in Python.
- Automating Repetitive Jobs: It could actually write scripts to automate frequent improvement duties, knowledge 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 improvement equipment (SDK).
- Translating Code Between Languages: It could actually 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 knowledge they want in plain language, and Codex can write the proper SQL queries.
- Making Easy Internet Constructions: It could actually create HTML and CSS for fundamental webpage layouts from descriptions.
What Drawback Does Codex Remedy?
Codex helps with a number of large difficulties and challenges in software program improvement and different areas:
- Saves Growth Time: By routinely creating frequent code, normal features, and even advanced procedures, Codex makes the event course of a lot sooner.
- 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 study by seeing how Codex turns their plain language descriptions into a brand new language or by asking it to elucidate current code.
- Automates Boring Coding Jobs: It frees builders from boring duties, to allow them to deal with 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 advanced design of huge language fashions (LLMs), notably the GPT collection. Right here’s an easier concept of the way it works:
- Transformer Design: Like different GPT fashions, Codex makes use of the Transformer neural community design. This design is excellent at understanding context and connections in collection of knowledge, like plain textual content and contours of code.
- Large Coaching Information: Codex was skilled on a really giant set of textual content and code. This included loads 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 different knowledge) 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, frequent coding methods, tips on how to 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 most probably collection of code “tokens” (the fundamental 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 complete applications.
- Understanding Context: An enormous energy is its capability 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 latest ChatGPT updates and the Codex CLI) use extra superior considering talents, such because the “o3” reasoning mannequin talked about in latest 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, take into account exploring our Immediate Engineering Course for ChatGPT.
Utilization Examples: Codex in Motion
The easiest way to see what Codex can do is thru examples, a lot of that are seen in precise makes use of and discussions:
1. Turning Plain Language into Code (Bouncing Ball Animation)
- Description: A fundamental capability is popping a easy concept into working code.
- Utilization Instance: A consumer might 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) # Pink
ball_rect = pygame.Rect(screen_width // 2 - ball_radius, screen_height // 2 - ball_radius, ball_radius * 2, ball_radius * 2)
dx, dy = 5, 5 # Velocity and route
clock = pygame.time.Clock() # For controlling velocity
whereas True:
for occasion in pygame.occasion.get():
if occasion.sort == pygame.QUIT:
pygame.give up()
sys.exit()
ball_rect.x += dx
ball_rect.y += dy
# Examine for hitting partitions
if ball_rect.left <= 0 or ball_rect.proper >= screen_width:
dx = -dx
if ball_rect.high <= 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) # Hold 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 bettering code, writing exams, or creating code proper of their ordinary work setup.
- Utilization Instance: A developer of their terminal:
codex --model o4-mini "Enhance the perform 'fetchData' in 'utils.ts' to make use of async/await and higher error dealing with."
If utils.ts had:
// utils.ts
perform fetchData(id: string) {
return fetch(`https://api.instance.com/knowledge/${id}`)
.then(res => {
if (!res.okay) {
throw new Error(`HTTP error! standing: ${res.standing}`);
}
return res.json();
});
}
Codex can counsel:
// utils.ts (improved by Codex)
async perform fetchData(id: string) {
strive {
const res = await fetch(`https://api.instance.com/knowledge/${id}`);
if (!res.okay) {
throw new Error(`HTTP error! standing: ${res.standing}`);
}
return await res.json();
} catch (error) {
console.error("Did not fetch knowledge:", error);
throw error; // Move the error to the half that referred to as this perform
}
}
The CLI would present the adjustments for evaluate, and the developer might settle for them.
3. Automating Jobs with Codex in ChatGPT (Bug Fixing)

Description: When a part of ChatGPT, Codex can act like a “digital workforce member,” doing software program engineering work like including options, fixing bugs, and creating pull requests in a protected, separate surroundings.
Utilization Instance: A developer connects Codex in ChatGPT to a GitHub venture and asks: “Repair the bug in payment_processing.py the place reductions for ‘PREMIUM’ customers don’t work if their cart complete is underneath $50.” Codex would:
- Copy the venture into its protected surroundings.
- Take a look at payment_processing.py to seek out the low cost guidelines.
- Discover the wrong situation.
- Counsel a repair, possibly by altering a situation or including a brand new one.
- Write or replace exams for this particular case.
- Run exams to examine the repair.
- Create a pull request with the code adjustments, check 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 advanced {hardware}, like programming robots.
Utilization Instance: A developer asks Codex: “Write a Python script utilizing the Unitree SDK to make the A1 robotic get up, 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 appropriate connection methodology
print("Robotic standing up...")
robotic.stand_up() # Concept of an SDK perform
robotic.wait_for_motion_complete()
print("Robotic strolling ahead...")
robotic.move_forward(distance=0.5, velocity=0.2) # Concept of an SDK perform
robotic.wait_for_motion_complete()
print("Robotic sitting down...")
robotic.sit_down() # Concept of an SDK perform
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 Categorical server with one GET endpoint '/standing' that returns { standing: 'okay' } as JSON."
The modified CLI, working with Gemini, can produce:
const categorical = require('categorical');
const app = categorical();
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 seek out the names and e-mail addresses of all prospects 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 might create:
SELECT c.CustomerName, c.Electronic mail
FROM Clients c
JOIN Orders o ON c.CustomerID = o.CustomerID
WHERE c.State="California"
AND o.OrderDate >= DATE('now', '-30 days');
Learn: Learn how to prepare Codex on a posh SQL legacy database mannequin
7. Writing Unit Assessments
- Description: Ensuring code is nice high quality by way of computerized testing.
- Utilization Instance: Given a Python perform:
def calculate_discount(value, proportion):
if not 0 <= proportion <= 100:
elevate ValueError("Low cost proportion have to be between 0 and 100.")
return value * (proportion / 100.0)
Immediate: “Write pytest unit exams for the Python perform calculate_discount.”
Codex can create:
import pytest
from your_module import calculate_discount # Assuming the perform 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 probably probably the most well-known use of Codex. GitHub Copilot works as an AI pair programmer inside code editors, providing real-time code ideas and completions.
- ChatGPT Integration: As proven within the X examples, Codex is being put extra deeply into ChatGPT. This lets customers give advanced coding jobs, ask questions on code, and handle software program tasks in a chat-like approach. These setups typically have protected, separate areas for operating and testing code.
- Codex CLI: The command-line instrument lets builders who like working in a terminal use Codex for code creation, evaluation, and adjustments proper of their native improvement setups.
- Codex and Microsoft Phrase (and different Workplace Apps): Whereas there might not be 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: Rapidly 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 additional areas from a doc. Whereas straight creating code inside Phrase for Phrase’s personal scripting (like VBA) with Codex is much less frequent, the fundamental pure language understanding and textual content creation are very helpful. Builders may make Workplace Add-ins that use the OpenAI API to convey Codex-like options into Phrase.
Information Science with OpenAI Codex
Codex is changing into a really useful instrument for knowledge scientists:
- Sooner Scripting: Information scientists can describe knowledge 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 whole 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 knowledge turns into simpler.
- Exploratory Information Evaluation (EDA): Codex can rapidly create small bits of code for frequent EDA jobs like checking for lacking data, getting fundamental statistics, or making first-look charts.
- Studying New Libraries: Information scientists can learn to use new libraries by asking Codex to create instance code for sure jobs.
- Automating Report Creation: Scripts to get knowledge, do analyses, and put outcomes into experiences might be drafted with Codex’s assist.
Codex is changing into a really useful instrument for knowledge scientists, able to aiding with many duties. In the event you’re seeking to construct a robust basis or advance your expertise in leveraging AI for knowledge evaluation, our complete e-Postgraduate Diploma in Synthetic Intelligence and Information Science by IIT Bombay can offer you in-depth coaching.
Advantages of Utilizing Codex
- Extra Productiveness: Enormously cuts down time spent on writing normal and repetitive code.
- Higher Studying: Acts as an interactive method to study programming languages, libraries, and concepts.
- Simpler Entry: Makes coding much less intimidating for novices and non-programmers.
- Fast Prototyping: Permits quick creation of working fashions from concepts.
- Concentrate on Greater Issues: Lets builders consider construction, logic, and consumer expertise as a substitute of routine coding.
- Consistency: Will help hold 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 excellent. It could actually 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 advanced, or are worded unclearly. It generally makes code that isn’t the perfect or is incorrect. It really works finest for clearly outlined jobs.
- Outdated Data: The mannequin’s data is predicated on its coaching knowledge, which has a closing date. It may not know concerning the very latest libraries, API adjustments, or safety points discovered after its final coaching.
- Safety Points: Codex may unintentionally create code with safety weaknesses if these kinds_of patterns had been in its coaching knowledge. Cautious safety checks are wanted for any code utilized in actual merchandise.
- Bias: Like all AI fashions skilled on giant web datasets, Codex can present biases from that knowledge. 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 absolutely understanding the code. This might decelerate their studying.
- Context Window: Whereas getting higher, LLMs can solely keep in mind a certain quantity of data. They could lose observe 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 skilled on current code), lack of jobs, and doable misuse for creating dangerous code are nonetheless being mentioned within the AI world.
- Security Throughout Operating (The way it’s Dealt with): As talked about, newer methods of utilizing Codex (like in ChatGPT and the Codex CLI) typically run in a protected, separate space with no web entry whereas a job is operating. This limits what it could possibly 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 provided to ChatGPT Professional, Enterprise, and Group 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 be doable by way of 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 improvement. We will anticipate:
- Smarter AI Coding Helpers: AI will get even higher at understanding what customers need, dealing with advanced 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.
- Automated Bug Fixing and Repairs: AI might tackle a bigger function find, understanding, and even fixing bugs in dwell programs.
- 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.
- Modifications in Developer Jobs: Builders will probably spend extra time defining issues, designing programs, guiding AI, and checking AI-made code, quite than writing each line by hand.
OpenAI sees a future the place builders give routine jobs to AI brokers like Codex. This may allow them to deal with larger plans whereas being extra productive. This implies working with AI in real-time, deeper connections with developer instruments (like GitHub, challenge trackers, and CI programs), and mixing dwell AI assist with assigning jobs that may be finished later.