Claude Code vs Codex (October 2026): Which One to Pick
Claude Code vs Codex in October 2026: models, pricing, usage limits, CLI, IDE and cloud workflows, strengths, weaknesses and a decision table to pick one.
Legacies is a software and web studio from Romania, founded by Horia Stan and Alexandru Talnaci, and we have paid for both Claude Code and Codex this year while shipping client sites and our own products. Both are good, at slightly different things.
The short answer: pick Claude Code if you live in the terminal and want deep control over context, instructions and automation. Pick Codex if you already pay for ChatGPT, want to hand off tasks to the cloud and check back later, or need a free way to start. Both cost $20 a month at the entry paid tier, and both meter usage in five-hour windows with weekly caps.
Quick answer
- Models: Claude Code defaults to Claude Opus 5.5 on paid plans. Codex defaults to GPT-6.1 Sol, released at OpenAI DevDay on September 29, 2026.
- Price: both start at $20 a month (Claude Pro, ChatGPT Plus). Codex also runs on ChatGPT Free and Go with a smaller model. Claude Code does not run on the Free plan.
- Workflow: Claude Code is terminal-first with strong local customization. Codex leans on cloud tasks, the ChatGPT desktop app and GitHub code review.
- Our take: many teams will end up using both, one as the daily driver and one as a second opinion on reviews.
Claude Code vs Codex at a glance
| Claude Code | OpenAI Codex | |
|---|---|---|
| Maker | Anthropic | OpenAI |
| Default model | Claude Opus 5.5 | GPT-6.1 Sol |
| Other models | Sonnet 5.5, Haiku 4.5, Fable 5.1 | GPT-6 Astra, GPT-6 Luna, GPT-6 Sol |
| Cheapest paid plan | Claude Pro, $20 a month | ChatGPT Plus, $20 a month |
| Free access | No | Yes, ChatGPT Free with GPT-6 Luna |
| Surfaces | Terminal, VS Code, JetBrains, desktop, web, mobile, Slack | ChatGPT desktop app, CLI, IDE extension, cloud, Slack and Teams |
| Instruction file | CLAUDE.md (also reads AGENTS.md) | AGENTS.md |
| Open-source CLI | No | Yes |
| Usage metering | 5-hour session plus weekly limit | 5-hour window plus weekly limits |
Sources: the Claude Code overview, Claude pricing, the Codex docs and Codex pricing, all checked at the time of writing.
Models: Opus 5.5 vs GPT-6.1 Sol
Claude Code models
On Pro, Max, Team, Enterprise and the API, Claude Code defaults to Claude Opus 5.5, according to the model configuration docs. You can switch to Sonnet 5.5 for everyday work, Haiku 4.5 for simple tasks, or Fable 5.1, which Anthropic positions for demanding reasoning and long-horizon agentic work. Fable is never the default, and on some plans it bills to usage credits.
Opus 5.5 and Sonnet 5.5 both have a 1 million token context window, which is great until you see how fast big context drains your limits.
Codex models
OpenAI announced GPT-6.1 Sol at DevDay on September 29, 2026, as a major upgrade to GPT-6 Sol for agentic coding. It became the default coding model in Codex shortly after. GPT-6 Astra sits above it for the hardest problems, and GPT-6 Luna handles fast, high-volume work. OpenAI also says GPT-5.5 retires from Codex on all plans on October 14, 2026.
API prices
If you run either tool with an API key, you pay per token. Prices per million tokens:
| Model | Input | Output |
|---|---|---|
| Claude Opus 5.5 | $4 | $20 |
| Claude Sonnet 5.5 | $2 | $10 |
| GPT-6.1 Sol | $2 | $10 |
Claude prices come from the Claude models overview. GPT-6.1 Sol's API price was announced at DevDay, with cached input at $0.10 per million tokens. On raw token price, Sol undercuts Opus. But an agent that solves a task in fewer turns can cost less overall.
Pricing and plans
| Tier | Claude (Claude Code) | ChatGPT (Codex) |
|---|---|---|
| Free | No Claude Code | Codex with GPT-6 Luna in the desktop app |
| Low cost | None | Go, $8 a month, GPT-6 Luna |
| Standard | Pro, $20 a month ($17 billed yearly) | Plus, $20 a month |
| Heavy use | Max 5x $100, Max 20x $200 | Pro at $100, $200 or $500 a month |
| Teams | Team Standard $25 a seat monthly, $20 yearly | Business, $20 a user a month billed yearly |
Codex's $500 Pro tier adds access to GPT-6 Astra Ultrafast. Claude's Max tiers give 5x or 20x the Pro session allowance.
Usage limits
Both tools use a rolling five-hour window plus weekly limits, and both share the budget with their chat app. That second part matters: a long ChatGPT or Claude conversation reduces what is left for coding.
The difference is transparency. OpenAI publishes rough ranges. On Plus, Codex estimates 15-160 local messages per five hours with GPT-6.1 Sol, 5-45 with GPT-6 Astra and 350-3,000 with GPT-6 Luna. Cloud tasks consume the allowance faster than local messages. Fast mode uses 2.5x your included limits.
Anthropic does not publish message counts. It describes Max as 5x or 20x Pro and tells you to watch your usage in Settings or with /usage. Since September 14, 2026, weekly limits in Claude Code are 25% higher than before Anthropic's summer promotion. We break down exactly how that works in Claude usage limits explained.
Workflow: terminal, IDE and cloud
Claude Code
Claude Code started as a terminal tool and still feels most at home there. It now also runs as a VS Code and JetBrains extension, a desktop app, on the web at claude.ai/code and on mobile. You can start a task in the cloud and pull it into your terminal with claude --teleport.
Where it stands out is customization. CLAUDE.md files carry project rules, path-scoped rules load only for matching files, skills package workflows, hooks run shell commands before or after actions, and subagents isolate noisy work. For a studio that wants the agent to follow house conventions, this is a real advantage.
Codex
Codex is built around delegation. You can work locally through the open-source CLI or IDE extension, but the strong move is Codex Cloud: tasks keep running while your laptop is closed and come back as finished changes. Codex also reviews pull requests on GitHub when you tag @Codex, and works inside ChatGPT on Slack and Teams. Instructions live in AGENTS.md, which Claude Code can also read, so one file can serve both tools.
Strengths and weaknesses
These are our impressions from daily work, not benchmark results. Your codebase will differ.
Where Claude Code is stronger
- Context control. Fine-grained tools to see, trim and shape what the model sees:
/context,/compact,/clear, rules, skills. - Automation and hooks. Easy to wire into scripts, CI and pre-commit checks.
- Long, careful refactors. Opus 5.5 is patient on multi-file changes when you give it a clear plan.
Where Claude Code is weaker
- No free tier. You need at least Pro to try it.
- Opaque limits. No published message counts, so heavy users learn their limits by hitting them.
- Costly defaults. Opus as the default model drains quota quickly on simple tasks unless you switch.
Where Codex is stronger
- Fire-and-forget cloud tasks. Good for parallel, well-scoped work you review later.
- Entry price. Free and $8 options let a curious founder start without a commitment.
- PR review on GitHub. Tagging
@Codexon a pull request is a cheap second reviewer.
Where Codex is weaker
- Less local customization than Claude Code's rules, hooks and skills stack, in our experience.
- Model churn. New models arrived twice in September 2026 alone, which can shift behavior under your feet.
- Cloud tasks eat limits fast, so the delegation model needs a bigger plan for heavy use.
Which one should you pick
| If you... | Pick |
|---|---|
| Want to try an AI coding agent for free | Codex |
| Already pay for ChatGPT Plus | Codex |
| Live in the terminal and script everything | Claude Code |
| Need the agent to follow strict house rules | Claude Code |
| Want to hand off tasks and review finished changes | Codex |
| Do long multi-file refactors with a plan | Claude Code |
| Want automatic PR review as a second opinion | Codex, alongside either |
| Prefer an editor-first experience | Neither first, see Cursor vs Claude Code |
If you are still choosing a broader stack, our roundup of the best vibe coding tools in 2026 covers app builders as well as coding agents.
Where a team fits in
Both tools are excellent at writing code. Neither is responsible for it. We use them daily on client work and our own products, and the pattern we see in projects that come to us is consistent: the prototype works, but authentication, data handling, deployment and security were never reviewed by a person who owns the result. Our post on vibe coding security risks lists the usual holes.
That review layer is the part a senior team adds. We still use the agents. We just read every diff before it ships.
When to do it yourself and when to bring in a team
Do it yourself if you are building a prototype, an internal tool or a side project, and you are willing to learn to review what the agent writes. Either tool at $20 a month is a bargain for that. The habits that make it work are in our post on how AI coding agents change small teams.
Bring in a team when real users, payments or personal data are involved, or when you need a fast website that ranks in Google and AI search, not a demo. Our services page lists fixed starting prices, from 1,499 lei (about EUR 285) for a landing page to 3,499 lei (about EUR 665) for a web app. If you already have a site, run the free website audit first.
Frequently Asked Questions
Is Claude Code better than Codex?
Neither is better for everyone. Claude Code is stronger for terminal-heavy work, strict project rules and long refactors, while Codex is stronger for delegating tasks to the cloud, reviewing pull requests on GitHub and starting for free. Try both on the same real task from your own codebase before deciding.
Can I use Codex for free?
Yes. At the time of writing, Codex is included on the ChatGPT Free plan with GPT-6 Luna in the desktop app, subject to rollout, and on the $8 Go plan. For the stronger GPT-6.1 Sol model and higher limits you need Plus at $20 a month or above.
Is Claude Code included in Claude Pro?
Yes. Claude Code is included in Claude Pro at $20 a month and in both Max plans. It is not included in the Free plan. Usage in Claude Code and the Claude app shares the same five-hour and weekly limits.
Which is cheaper, Claude Code or Codex?
At the entry level they cost the same, $20 a month for Claude Pro or ChatGPT Plus. Codex is cheaper to start because it has Free and $8 Go options. On the API, GPT-6.1 Sol costs $2 input and $10 output per million tokens, half of Claude Opus 5.5 and the same as Claude Sonnet 5.5.
Can I use Claude Code and Codex on the same project?
Yes, and many teams do. Claude Code can read an AGENTS.md file, which is what Codex uses for instructions, so one instruction file can serve both. A common setup is one tool as the daily coding agent and the other as an automatic pull request reviewer.
What model does Codex use now?
Codex defaults to GPT-6.1 Sol, which OpenAI announced at DevDay on September 29, 2026. GPT-6 Astra is available for harder problems and GPT-6 Luna for fast, high-volume work. GPT-5.5 retires from Codex on October 14, 2026.