Menu

Zelili AI

GPT-5.3-Codex

From OpenAI

OpenAI’s Most Capable Agentic Coding Model – Frontier Performance with Interactive Collaboration and Full Software Lifecycle Support
Tool Release Date

5 Feb 2026

Tool Users
700 Million+
0.0

Pricing Model

Starting Price

$20/Month

Visit GPT-5.3-Codex
👁 247

About This AI

GPT-5.3-Codex is OpenAI’s latest frontier agentic coding model released on February 5, 2026, combining top coding capabilities from GPT-5.2-Codex with enhanced reasoning and professional knowledge from GPT-5.2 in a single faster model.

It runs 25 percent faster than predecessors and supports long-horizon tasks involving research, tool use, complex execution, and autonomous iteration over millions of tokens.

Key strengths include interactive collaboration: users steer mid-execution, ask questions, provide feedback, and stay in the loop without losing context.

The model excels at end-to-end software development: building full apps/games from scratch (e.g., racing/diving games with maps, items, mechanics), web development with sensible defaults (pricing toggles, testimonials, carousels), debugging, deployment, monitoring, writing PRDs, editing copy, user research, tests, metrics, and even non-coding tasks like slide decks or data analysis.

It achieves state-of-the-art results on SWE-Bench Pro (56.8 percent), Terminal-Bench 2.0 (77.3 percent), OSWorld-Verified (64.7 percent), and strong cybersecurity benchmarks.

First model instrumental in its own creation: Codex team used early versions to debug training, manage deployment, and diagnose results.

Classified as High capability under Preparedness Framework, with comprehensive cybersecurity safety stack including vulnerability identification training.

Available to paid ChatGPT users via Codex app, CLI, IDE extension, and web; API access coming soon; 25 percent faster inference for Codex users.

Ideal for developers, engineers, and professionals needing a reliable coding collaborator for complex, multi-step projects across the full software lifecycle.

Key Features

  1. Agentic coding excellence: Handles long-running, multi-step tasks with research, tool use, and complex execution autonomously
  2. Interactive collaboration: Mid-turn steering, frequent updates, real-time feedback, and user-guided corrections without context loss
  3. Full software lifecycle support: From ideation and PRDs to coding, debugging, deployment, monitoring, and metrics
  4. 25 percent faster inference: Optimized speed for Codex users with fewer tokens per task
  5. Strong multi-language coding: Top performance across languages on contamination-resistant benchmarks
  6. Terminal and OS interaction: Advanced terminal skills and visual desktop/computer-use capabilities
  7. Non-coding professional tasks: Builds slide decks, analyzes spreadsheets, edits copy, conducts user research
  8. Cybersecurity focus: Trained to identify vulnerabilities with safety mitigations and monitoring
  9. Self-improvement precedent: Used internally to debug its own training and deployment
  10. Cross-surface availability: Codex app, CLI, IDE extensions, web; API soon

Price Plans

  1. Free ($0): Not available for GPT-5.3-Codex; basic ChatGPT free tier uses lighter models
  2. ChatGPT Plus ($20/Month): Access to GPT-5.3-Codex via Codex app, CLI, IDE extension, web with usage limits
  3. ChatGPT Pro/Business/Enterprise (Custom ~$200+/Month or token-based): Higher limits, priority access, API (coming soon), and advanced features for heavy use

Pros

  1. Frontier benchmarks leadership: SOTA on SWE-Bench Pro, Terminal-Bench 2.0, OSWorld-Verified, and cybersecurity CTFs
  2. Interactive and steerable: Acts like a colleague with real-time updates and feedback loops
  3. End-to-end autonomy: Builds complex apps/games over days with minimal hand-holding
  4. Speed and efficiency: 25 percent faster with fewer tokens for same or better results
  5. Versatile beyond code: Handles presentations, data analysis, research, and professional knowledge work
  6. Safety-conscious: High capability classification with layered cybersecurity protections
  7. Immediate access for paid users: Live now in Codex surfaces; API forthcoming

Cons

  1. Paid-only full access: Requires ChatGPT Plus/Pro/Business/Enterprise for Codex surfaces
  2. API not yet available: Coming soon but not immediate for custom integrations
  3. Compute-intensive for max effort: High reasoning modes slower on complex tasks
  4. Cybersecurity gating: Mitigations may limit certain dual-use scenarios
  5. No free tier for Codex: Basic ChatGPT free access doesn't include this model
  6. Potential for artifacts: Long autonomous runs may need steering to avoid issues
  7. Recent release: Limited real-world adoption stats or community examples yet

Use Cases

  1. Complex software development: Build full apps/games from scratch with autonomous iteration and debugging
  2. Web and frontend engineering: Create responsive sites with pricing toggles, carousels, testimonials, and modern aesthetics
  3. DevOps and infrastructure: Automate deployment, monitoring, and metrics tracking
  4. Professional knowledge work: Generate slide decks, analyze spreadsheets, write PRDs, or conduct user research
  5. Cybersecurity tasks: Identify vulnerabilities, support defense research, and CTF challenges
  6. Agentic workflows: Long-horizon projects requiring research, tool use, and multi-step execution
  7. Team collaboration: Interactive coding partner for debugging, planning, and iteration

Target Audience

  1. Software engineers and developers: Needing advanced coding agents for full lifecycle tasks
  2. Product and engineering teams: Building prototypes, debugging, and automating workflows
  3. DevOps and infrastructure engineers: Handling deployment, monitoring, and metrics
  4. Cybersecurity researchers: Vulnerability identification and defense acceleration
  5. Professionals in knowledge work: Creating presentations, analyzing data, writing docs
  6. Enterprises and power users: Requiring high-limit, agentic AI via paid/API access

How To Use

  1. Access in ChatGPT: Log into chatgpt.com with paid plan; use Codex surfaces (app, CLI, IDE extension, web)
  2. Start a task: Prompt with project description (e.g., 'build a racing game with maps and items')
  3. Steer interactively: Ask questions, give feedback ('fix the bug', 'improve UI'), or steer mid-execution
  4. Monitor progress: Receive frequent updates; intervene to course-correct without losing context
  5. Use tools: Let it research, call tools, or operate computer for end-to-end tasks
  6. Download Codex app: macOS app at persistent.oaistatic.com/codex-app-prod/Codex.dmg for desktop use
  7. API (soon): Integrate via OpenAI API once enabled for custom agents/workflows

How we rated GPT-5.3-Codex

  • Performance: 4.9/5
  • Accuracy: 4.8/5
  • Features: 4.9/5
  • Cost-Efficiency: 4.5/5
  • Ease of Use: 4.6/5
  • Customization: 4.7/5
  • Data Privacy: 4.5/5
  • Support: 4.6/5
  • Integration: 4.7/5
  • Overall Score: 4.8/5

GPT-5.3-Codex integration with other tools

  1. Codex Surfaces: Native access via Codex app (macOS), CLI, IDE extensions (VS Code etc.), and web interface
  2. OpenAI API (coming soon): For custom agents, workflows, and enterprise integrations
  3. Terminal and OS Environments: Strong interaction with terminals, browsers, and desktop for agentic computer-use
  4. Development Tools: Works seamlessly with GitHub, Vercel, and other dev platforms for deployment and testing
  5. Collaboration Platforms: Potential for sharing outputs in Slack, Teams, or Notion via manual/API

Best prompts optimised for GPT-5.3-Codex

  1. Build a complete responsive web app for a fitness tracker with user dashboard, progress charts, goal setting, and subscription pricing toggle; use modern design with dark mode support
  2. Create a 2D racing game in browser with multiple racers, procedurally generated maps, power-ups, collision physics, and leaderboard; iterate until playable and bug-free
  3. Generate a 10-slide PowerPoint presentation on financial risks of rolling CDs into variable annuities, citing FINRA and NAIC sources, with clear visuals and bullet points
  4. Debug and optimize this existing codebase [paste code]; find vulnerabilities, improve performance, add tests, and deploy to Vercel with monitoring setup
  5. Act as my coding partner: research best practices for React 19 hooks, build a todo app with authentication, real-time sync, and dark mode; explain each step and ask for feedback
GPT-5.3-Codex sets a new bar for agentic coding, combining frontier performance with interactive collaboration for full software lifecycle tasks. Its speed, reliability on tough benchmarks, and ability to build complex apps autonomously make it a game-changer for developers. Paid access only, but essential for serious engineering and professional work.

FAQs

  • What is GPT-5.3-Codex?

    GPT-5.3-Codex is OpenAI’s most capable agentic coding model released February 5, 2026, combining frontier coding with reasoning and professional knowledge in a 25 percent faster package.

  • When was GPT-5.3-Codex released?

    It was officially introduced and made available on February 5, 2026, for paid ChatGPT users via Codex surfaces.

  • What are the key benchmarks for GPT-5.3-Codex?

    It achieves 56.8 percent on SWE-Bench Pro, 77.3 percent on Terminal-Bench 2.0, 64.7 percent on OSWorld-Verified, and strong results on cybersecurity CTFs.

  • How fast is GPT-5.3-Codex?

    It runs 25 percent faster than predecessors with fewer tokens for equivalent or better results.

  • Is GPT-5.3-Codex free to use?

    No, it requires a paid ChatGPT plan (Plus/Pro/Business/Enterprise) for access via Codex app, CLI, IDE extension, or web; API coming soon.

  • What makes GPT-5.3-Codex unique?

    It supports interactive mid-execution steering, long-horizon autonomy, and full software lifecycle tasks; first model used to help build itself.

  • Where can I access GPT-5.3-Codex?

    Available now in Codex app (macOS), CLI, IDE extensions, and web for paid users; download app at persistent.oaistatic.com/codex-app-prod/Codex.dmg.

  • Does GPT-5.3-Codex handle non-coding tasks?

    Yes, it excels at slide decks, spreadsheet analysis, copy editing, user research, and other professional knowledge work.

Newly Added Tools​

Qodo AI

$0/Month

Codiga

$10/Month

Tabnine

$59/Month

CodeRabbit

$0/Month
GPT-5.3-Codex Alternatives

Qodo AI

$0/Month

Codiga

$10/Month

Tabnine

$59/Month

Latest AI News

GPT-5.3-Codex Reviews

0.0
0.0 out of 5 stars (based on 0 reviews)
Excellent0%
Very good0%
Average0%
Poor0%
Terrible0%

There are no reviews yet. Be the first one to write one.