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

Tabnine
Tabnine's own models (local + cloud)
Tier-list head-to-head. Codex (OpenAI) takes the A-tier slot — here's the breakdown.
Spec sheet
| Tier | A-tierwin | C-tier |
| Overall score | 8.3 / 10win | 6.3 / 10 |
| Powered by | GPT-5.2-Codex (default 2026-04-23) / GPT-5.5 / GPT-5.4 | Tabnine's own models (local + cloud) |
| 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. | Enterprise teams in regulated industries (healthcare, finance) who need AI code completion that stays on-pr… |
| 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 — Tabnine 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)Enterprise teams in regulated industries (healthcare, finance) who need AI code completion that stays on-premise.
Visit TabnineBottom line
Codex (OpenAI) is the clear winner: 8.3/10 (A-tier) versus 6.3/10 (C-tier). Tabnine isn't a bad tool, but on every category that drives the overall score, Codex (OpenAI) comes out ahead. The tier gap is repeatable -- not methodology noise -- and the day-to-day experience reflects it.
Pricing-wise, both tools have a free tier (Codex (OpenAI) starts $0, Tabnine 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 Tabnine when enterprise teams in regulated industries (healthcare, finance) who need ai code completion that stays on-premise. 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 Tabnine's lane, the score gap matters less than the fit.
Bottom line: Codex (OpenAI) is the better tool for most people right now. Pick Tabnine only when enterprise teams in regulated industries (healthcare, finance) who need ai code completion that stays on-premise -- that's its lane, and inside that lane it still earns its place.
Keep digging
Full Codex (OpenAI) review
Tier A · 8.3/10
Full Tabnine review
Tier C · 6.3/10
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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.