Google Antigravity vs OpenAI Codex: Pricing, Models, Which to Use

Google Antigravity and OpenAI Codex are both agentic coding tools that can write, edit, run and review code on their own, but they aren't really competing on the same models. Antigravity is Google's multi-model agent IDE: its core models are Gemini, it offers Claude as a paid add-on, and the only OpenAI model it includes is GPT-OSS-120b, an open-weight model, not OpenAI's own Codex-branded models. Codex is OpenAI's first-party coding agent, bundled into ChatGPT and built around OpenAI's latest GPT-6 family. For most developers, the honest short answer is: pick Antigravity if you want one tool that can call Gemini, Claude and an open OpenAI model from a single subscription; pick Codex if you're already paying for ChatGPT and want OpenAI's own models with the deepest GitHub, Slack and cloud-sandbox integration.

What is Google Antigravity?

Google Antigravity is Google's agentic development platform, available as a desktop app, a terminal CLI, and extensions for Visual Studio Code, Visual Studio, JetBrains IDEs, Zed, Xcode and Eclipse (plus other editors over the Agent Client Protocol). It lets an agent plan multi-step changes, run code in a sandboxed terminal, browse the web, generate UI mockups with Nano Banana 2, and hand off work to subagents for parallel tasks. Instead of being tied to one AI lab, Antigravity's model picker spans several providers at once. Inside a session, you can set a "thinking level" of Low, Medium or High per task, trading faster responses on quick edits for deeper multi-step reasoning on larger architecture or debugging work, and your chosen reasoning model persists across turns in the same conversation until you switch it or cancel the run.

What is OpenAI Codex?

Codex is OpenAI's own coding agent, built into ChatGPT rather than sold as a separate product. It's available as a CLI, an IDE extension, a cloud environment ("Codex Cloud") that runs tasks in isolated sandboxes, a GitHub Action for CI, and an SDK/App Server for building custom integrations. Because Codex usage and ChatGPT usage share the same plan and credits, anyone who already has ChatGPT Plus or Pro gets Codex access included rather than as an add-on. Codex can also run in a non-interactive, headless mode for scripted automation, and OpenAI's documentation describes dedicated setup paths for GitHub, GitLab (in beta), Slack and Linear, so a Codex task can be triggered from, or report back into, tools a team is already using day to day.

Pricing compared

Both tools are sold as part of a broader AI subscription rather than priced standalone, which makes the comparison less obvious than it looks.

One practical difference: Antigravity has no bring-your-own-key or BYO-endpoint option at any tier, according to Google's own plans documentation. Codex, by contrast, can run entirely on a pay-as-you-go API key with no ChatGPT subscription at all, which matters for CI pipelines and automation that shouldn't share a human's usage quota.

Which AI models you actually get

This is where the two tools diverge most, and where it's easy to overstate what each one includes. On the free and Plus tiers, Antigravity's core agent model is Gemini 3.8 Flash. Paying for Google AI Pro unlocks Gemini 4 Argon (or on a trial with eligible devices) plus Claude Sonnet 5.5 and Claude Opus 5.5 "thinking" models for non-trial subscribers. Google AI Ultra and Enterprise add Gemini 4 Carbon and, on Enterprise only, Gemini 3.1 Pro and the older Gemini 3.6/3.7 Flash tiers. The only OpenAI-branded option inside Antigravity is GPT-OSS-120b, OpenAI's open-weight model — not the proprietary GPT-6 family that powers ChatGPT and Codex. Google's own model availability chart also flags that Claude Sonnet 4.6 and Opus 4.6 "will be removed on November 18, 2026," so anyone relying on those two specifically should plan to move to Claude 5.5 or a Gemini model before that date.

Codex's models are exclusively OpenAI's own: GPT-6.1 Sol and GPT-6 Luna are the current defaults across plans, and GPT-6.1 Terra — aimed at visual reasoning and computer use — rolled out to ChatGPT Work and Codex on Plus, Pro, Business, Enterprise and Edu plans in early November 2026, per OpenAI's developer documentation. GPT-5.5 was retired from Codex sessions that sign in with a ChatGPT account on October 14, 2026, though sessions authenticated with an API key kept access on the old pricing. There's no Gemini or Claude option inside Codex at all — if you want a specific non-OpenAI model, Codex isn't the tool for it.

IDEs and surfaces supported

Antigravity ships a standalone desktop app plus a CLI, and its IDE extensions cover Visual Studio Code, Visual Studio, JetBrains IDEs (IntelliJ, PyCharm, etc.), Zed, Xcode and Eclipse, with other editors reachable through the Agent Client Protocol. Codex instead layers onto ChatGPT's existing surfaces — ChatGPT desktop, web and mobile apps — and adds its own CLI, a dedicated IDE extension, and Codex Cloud for sandboxed cloud runs, plus a GitHub Action for CI and an SDK/App Server for custom tooling. If your workflow already lives inside JetBrains or Zed, Antigravity has first-party support those editors; if it lives inside GitHub Actions, Slack or Linear, Codex's third-party integrations are more built-out.

Agentic workflow features

Both agents can plan multi-step work, edit across files, and run commands in a sandbox rather than directly on your machine. Antigravity adds subagents and a "/swarm" mode (currently in preview) for parallel multi-agent orchestration, Remote Control for driving a desktop or CLI session from a browser, and a Python SDK for building custom agents and lifecycle hooks. Codex supports Git worktrees for running several tasks on the same repo in parallel, local and cloud ("Codex Cloud") execution modes, non-interactive/headless automation, an auto-review feature for pull requests, and a separate Codex Security plugin for running vulnerability scans and triaging findings. Neither vendor publishes independently verified head-to-head benchmark scores for coding tasks, and no outside lab has published a controlled comparison between the two as of this writing, so treat any specific speed or accuracy claim you see elsewhere with caution. What is documented is the retirement schedule for each side's older models: OpenAI retired GPT-5.5 from ChatGPT-signed-in Codex sessions on October 14, 2026, and Google is retiring Claude Sonnet 4.6 and Opus 4.6 from Antigravity on November 18, 2026 — so a task you automate against a specific model name today is worth revisiting before either deadline.

Data privacy and age requirements

The two products also differ on account rules worth knowing before you sign up. Google's own Antigravity FAQ states that Antigravity "is unavailable to users under 18" on any plan, including the free tier, and that users can opt out of data collection at any point from the Settings panel — though Google points to its Terms of Service rather than the FAQ itself for the specifics of what's collected by default. The same FAQ also notes that logging into third-party coding agents (it names Claude Code, OpenClaw and OpenCode specifically) with an Antigravity account isn't supported — your Antigravity sign-in is meant to stay inside Google's own surfaces.

OpenAI's Codex pricing page states that its Business plan comes with "no training on your business data by default," and Enterprise/Edu tiers add SCIM, domain verification, and role-based access control on top of that. Codex doesn't carry a stated minimum age separate from ChatGPT's own account rules. Treat both of these as starting points, not full policies — read the linked Terms of Service or data-processing terms directly if data handling is a deciding factor for your team.

Which should you choose?

If you're already paying for Google AI Pro or Ultra for Gemini elsewhere, Antigravity is close to free additional value, and Google AI Pro at $19.99/mo is the cheaper way to get occasional Claude access alongside Gemini. If your team is standardized on JetBrains or Zed, Antigravity's native extensions are also a practical draw. If you're already a ChatGPT Plus or Pro subscriber, Codex is similarly close to free additional value, and its deeper GitHub Action, Slack and cloud-sandbox integrations make it the stronger pick for CI-heavy teams — doubly so if you want a pay-as-you-go API key with no subscription at all. Neither tool is a strict upgrade over the other; the real decision driver is which model family and which existing subscription you're already committed to.

A few concrete scenarios: a solo developer who only wants Gemini and doesn't care about Claude or GPT models can stay on Antigravity's free tier indefinitely. A developer who wants occasional access to both Gemini and Claude from one login, without paying for two separate chatbot subscriptions, gets more out of Google AI Pro at $19.99/mo than out of stacking a Claude subscription on top of ChatGPT. A team that automates code review inside GitHub Actions or needs an unattended CI agent is better served by Codex's API-key option, since Antigravity has no equivalent pay-per-use path. And anyone under 18 is locked out of Antigravity entirely regardless of which plan they'd otherwise pick, which makes Codex (bundled into ChatGPT's own age rules) the only option of the two for younger students using a coding agent.

What's next

Watch two dates: November 18, 2026, when Antigravity drops Claude Sonnet 4.6 and Opus 4.6 (Claude 5.5 remains on Pro and Ultra), and the continued rollout of GPT-6.1 Terra across more Codex and ChatGPT Work plans. Both vendors update their model lineups frequently enough that a plan comparison made today may shift within weeks — check Google's Antigravity plans page and OpenAI's Codex pricing page directly before committing to a paid tier. For a closer look at how Antigravity stacks up against two other popular agents, see our Antigravity vs Claude Code comparison and our Antigravity vs Cursor breakdown, or read how Antigravity's own terminal client compares to Google's other CLI in our Antigravity CLI vs Gemini CLI guide.

Written byFelix Moreau

Felix Moreau writes Pandromeda's software coverage and how-to guides. He covers Windows, macOS and Linux updates, the apps people rely on, emulators and developer tools, and turns official documentation into clear, numbered steps that work on the current version.

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