The best AI for coding is not just a model. It is a model running inside an agent that can write files, run them and check the result. So we tested the two that matter most in 2026, Claude Code and OpenAI's Codex, each with two of its vendor's top models, on identical briefs. Below are the builds. The verdict is short, and you can check it in a minute.
Which AI is best for coding?
Claude Opus 5.5 in Claude Code if you want the most finished result and can wait; GPT-6.1 Sol in Codex if you want a good result quickly and cheaply. That is the pattern across all eight of our briefs, from a landing page to a top-down MOBA. The table is live and aggregates every build we have recorded.
| Model | Briefs finished | Median wall time | Output tokens, all briefs | Average API-equivalent cost per build | Runtime errors | Interrupted attempts |
|---|---|---|---|---|---|---|
| Claude Opus 5.5 | 7 of 8 | 1h 14m | 1.8M (+1 not recorded) | $14.53 | 0 | 5 |
| Claude Fable 5.1 | 8 of 8 | 36m 57s | 1.3M | $13.85 | 0 | 5 |
| GPT-6 Astra | 8 of 8 | 11m 29s | 340k | $3.90 | 0 | 0 |
| GPT-6.1 Sol | 8 of 8 | 12m 05s | 394k | $0.80 | 0 | 0 |
The trade-off is stark. The Claude setups took from 25 minutes to two and a half hours per build and, at list API prices, cost about $7 to $25 each. The GPT setups finished in 7 to 25 minutes for $0.54 to $7.27. All four produced working software on every brief we have published.
Is Claude the best AI for coding?
On thoroughness, yes. Claude Code ran its own builds in a browser again and again: Opus 5.5 made 28 shell commands and 59 file reads for one landing page, and its builds are the most elaborate, such as a working booking calendar built into a landing page's hero. On speed, price and predictability, no. The GPT models did less, faster, and their two builds of any brief often looked like twins. If your time is worth more than your tokens, the Claude result is the better first draft. If you iterate anyway, Sol gets you to the second draft sooner.
What does each AI coding tool cost?
Two ways to pay. Subscriptions: Claude Code comes with Claude Pro, from $17 a month billed annually or $20 monthly according to Claude's pricing page, and OpenAI lists Codex on its ChatGPT Pro plans and Business seats. Pay-as-you-go: per-token API pricing from Anthropic and OpenAI. Agent work is token-hungry, so heavy users should expect to hit subscription limits; two of our maximum-effort Claude runs side by side exhausted a five-hour usage window in about two hours.
Which AI is best for which coding job?
Pick by the job, not the leaderboard. For marketing pages, see best AI for web design and best AI for building websites. For a direct model-by-model recommendation with API costs, read best LLM for coding. And if you would rather not take anyone's word for it, the blind test below hides the names until you have chosen.
Four 3D shooters, one prompt, names hidden. Which AI built the one you would keep?
Take the blind test
Frequently asked questions
What is the best AI for coding right now?
For the most complete first draft, Claude Opus 5.5 in Claude Code. For speed and cost, GPT-6.1 Sol in OpenAI's Codex. On our briefs Opus built the most elaborate results at 3 to 11 times the time, while Sol finished every build in under 15 minutes for about a dollar or less at list prices.
Is Claude the best AI for coding?
On thoroughness, the Claude models led: they tested their own work dozens of times and shipped the most feature-rich builds. On speed, price and consistency, the GPT models led. Best depends on whether your bottleneck is quality of the first draft or time and money.
Do I need a paid plan to use these AI coding tools?
Yes, for the agent versions. Claude Code starts with Claude Pro at $17 a month billed annually. OpenAI lists Codex on its ChatGPT Pro plans, from $100 a month, and on Business seats, and Plus subscribers can use their allowance in participating tools. Both agents can also be billed per token through each vendor's API.
How did you test the AIs?
Same prompt word for word, one attempt each, maximum reasoning effort, a 150-minute cap and no human edits. Every build was recorded with the same script and is published unedited, with the exact commands on our methodology page.