Codex (OpenAI)
Free tier available
- Free$0
- Go$8/mo
- Plus$20/mo
Our pickCodex (OpenAI)
GPT-5.2-Codex (default 2026-04-23) / GPT-5.5 / GPT-5.4

Julius AI
Tier-list head-to-head. Codex (OpenAI) takes the A-tier slot — here's the breakdown.
Spec sheet
| Tier | A-tierwin | B-tier |
| Overall score | 8.3 / 10win | 7.5 / 10 |
| Powered by | GPT-5.2-Codex (default 2026-04-23) / GPT-5.5 / GPT-5.4 | — |
| Free tier | Yes | Yes |
| Starting price | $0 | $0 |
| Best for | Developers already paying for ChatGPT Plus who want a coding agent at no extra cost. | Non-technical people who need to quickly analyze spreadsheets and create charts without learning SQL or Python. |
| Last reviewed | 2026-04-25 | 2026-03-27 |
Head-to-head
Rated 1-10 on the same rubric across all 130 tools we cover.
What you'll pay
Look past the headline number -- entry-tier limits drive most cost surprises.
Free tier available
Free tier available
GPT-5.2-Codex (launched 2026-04-23 -- SOTA on SWE-Bench Pro and Terminal-Bench 2.0; first-party scores below pending detailed third-party verification) benchmarks — Julius AI has no published benchmarks
| Benchmark | Description | Score |
|---|---|---|
| SWE-bench | Real GitHub issue fixing | 72% |
| HumanEval | Python code generation | 95% |
The decision
Use-case anchors and category strengths, side by side.
Developers already paying for ChatGPT Plus who want a coding agent at no extra cost. Especially good for parallel task execution -- assign multiple bug fixes or feature branches and let Codex work them simultaneously.
Visit Codex (OpenAI)Non-technical people who need to quickly analyze spreadsheets and create charts without learning SQL or Python.
Visit Julius AIBottom line
Codex (OpenAI) edges out Julius AI by 0.8 points (8.3 vs 7.5) -- a A-tier vs B-tier split that's narrow but real. Not a blowout; both belong on a shortlist. The score gap shows up most clearly in the categories that matter for Codex (OpenAI)'s strengths, so if those categories are your priority, the lead translates.
Pricing-wise, both tools have a free tier (Codex (OpenAI) starts $0, Julius AI starts $0), so you can test either without committing. Compare what each free tier actually unlocks -- usage caps, model access, and feature gates differ a lot more than the headline price suggests, especially as both vendors have tightened limits in 2026.
By use case: pick Codex (OpenAI) when developers already paying for chatgpt plus who want a coding agent at no extra cost. Pick Julius AI when non-technical people who need to quickly analyze spreadsheets and create charts without learning sql or python. The two tools aren't fighting for the same person -- they're aiming at adjacent jobs that occasionally overlap. If you're squarely in Codex (OpenAI)'s lane, the tier-list ranking and the use-case fit point the same direction; if you're in Julius AI's lane, the score gap matters less than the fit.
Bottom line: Codex (OpenAI) is the safer default for most readers, but Julius AI is competitive enough that the tie-breaker is your specific workload, not the spec sheet.
Keep digging
Full Codex (OpenAI) review
Tier A · 8.3/10
Full Julius AI review
Tier B · 7.5/10
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Built from our daily AI-tool sweep, last touched April 25, 2026. Honest tier-list reviews — no affiliate-link pieces disguised as advice. See the rubric or how we review.