GPT-5.2-Codex vs o3 Mini High
GPT-5.2-Codex leads o3 Mini High on the Artificial Analysis Intelligence Index, 28.5 to 11.0, and o3 Mini High costs 3.2x less per output token ($4.40 vs $14.00 per million). Updated October 21, 2026; 1 benchmarks have a result for both.
GPT-5.2-Codex or o3 Mini High: which to pick
Only GPT-5.2-Codex has a coding score, 45.4 on the Vibe Coding Index; o3 Mini High has none, so the two cannot be ranked on coding.
Pick o3 Mini High for output tokens 3.2x cheaper ($4.40 vs $14.00 per million).
- Shared results
- 1
- GPT-5.2-Codex only
- 21
- o3 Mini High only
- 2
- Like-for-like categories
- 1 of 9
Only benchmarks that tested both models count toward a pick; a result only one model has is shown but not compared.
Which one for your work
Each card is decided by one number both models carry. Where only one has it, the card says so and makes no call.
Coding
Vibe Coding Index, six public coding benchmarks
No call
Only GPT-5.2-Codex has a coding score, so no call is made.
One side not measured
Intelligence
AA Intelligence Index
GPT-5.2-Codex
GPT-5.2-Codex leads, 28.5 against 11.0.
Same board, both measured
Agentic work
AA Agentic Index
No call
Only o3 Mini High has a AA Agentic Index result, 0.9.
Directional only
Long documents
Listed context window
GPT-5.2-Codex
GPT-5.2-Codex takes 400K tokens against 200K.
Listed by OpenRouter
Everyday cost
1K input + 500 output tokens
o3 Mini High
GPT-5.2-Codex $0.0088, o3 Mini High $0.0033 per turn.
List prices
Cost per solved task
One SWE-bench Verified task, solved
No call
Only GPT-5.2-Codex has the number, $0.43.
Directional only
At a glance
- Coding index
- GPT-5.2-Codex 45.4 from 3 benchmarks, o3 Mini High not benchmarked.
- Widest category
- Intelligence, 17.5 points apart on average over 1 shared benchmark.
- Widest single gap
- AA Intelligence Index: GPT-5.2-Codex 28.5 against o3 Mini High 11.0, 17.5 points apart on a 0 to 100 scale.
- Output price
- GPT-5.2-Codex $14.00 against o3 Mini High $4.40 per million output tokens, 3.2x apart.
- Context window
- GPT-5.2-Codex takes 400K tokens, o3 Mini High 200K.
Benchmark by benchmark
First the score: boards each model leads, per category, where both have a result. Then every board, a category to a fold; bars are each result on a 0 to 100 scale, so compare the two in a row, not one row with another.
| Category | GPT-5.2-Codex | Bars | o3 Mini High | Ties |
|---|---|---|---|---|
| Intelligence | 1 | 0 | ||
| All shared boards | 1 | 0 |
CodingDirectional onlySix of these boards feed the Vibe Coding Index12 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| SWE-bench Verified | 72.8% | Not measured | Only GPT-5.2-Codex measured |
| SWE-bench Multilingual | 66.3% | Not measured | Only GPT-5.2-Codex measured |
| LMArena WebDev | 1339 | Not measured | Only GPT-5.2-Codex measured |
| AA Coding Index | Not measured | 16.3 | Only o3 Mini High measured |
| LiveCodeBench (Vals AI) | 88.0% | Not measured | Only GPT-5.2-Codex measured |
| SWE-bench Verified (Vals AI) | 72.4% | Not measured | Only GPT-5.2-Codex measured |
| Vibe Code Bench (Vals AI) | 37.9% | Not measured | Only GPT-5.2-Codex measured |
| Terminal-Bench Hard (Artificial Analysis run) | 37.1% | Not measured | Only GPT-5.2-Codex measured |
| Terminal-Bench | 66.5% | Not measured | Only GPT-5.2-Codex measured |
| ALE-Bench | 1299.9 | Not measured | Only GPT-5.2-Codex measured |
| LMArena WebDev: React | 1329 | Not measured | Only GPT-5.2-Codex measured |
| LMArena WebDev: HTML | 1348 | Not measured | Only GPT-5.2-Codex measured |
| Neither model has a result on the other 26 boards here | |||
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index10
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| AA Intelligence Index | 28.5 | 11.0 | GPT-5.2-Codex |
| Neither model has a result on the other 1 board here | |||
Agentic workDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| AA Agentic Index | Not measured | 0.9 | Only o3 Mini High measured |
| Design Arena: agents building web apps | 1051 | Not measured | Only GPT-5.2-Codex measured |
| Design Arena: agents building full-stack apps | 993 | Not measured | Only GPT-5.2-Codex measured |
| Design Arena: agents building mobile apps | 1090 | Not measured | Only GPT-5.2-Codex measured |
| Design Arena: agents building Android apps | 1176 | Not measured | Only GPT-5.2-Codex measured |
| Design Arena: agents building Godot games | 1142 | Not measured | Only GPT-5.2-Codex measured |
| τ²-Bench Telecom | 92.1% | Not measured | Only GPT-5.2-Codex measured |
| Neither model has a result on the other 32 boards here | |||
ReasoningDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| GPQA Diamond (Artificial Analysis run) | 89.9% | Not measured | Only GPT-5.2-Codex measured |
| Humanity's Last Exam (Artificial Analysis run) | 35.7% | Not measured | Only GPT-5.2-Codex measured |
| Neither model has a result on the other 19 boards here | |||
MathNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| Neither model has a result on 13 boards here | |||
KnowledgeNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| Neither model has a result on 17 boards here | |||
Web designNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| Neither model has a result on 9 boards here | |||
GeneralDirectional onlyPublic boards, shown as published, kept out of the index2 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| IFBench | 77.6% | Not measured | Only GPT-5.2-Codex measured |
| Long context reasoning (AA-LCR) | 82.3% | Not measured | Only GPT-5.2-Codex measured |
| Neither model has a result on the other 44 boards here | |||
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
| Benchmark | GPT-5.2-Codex | o3 Mini High | Leader |
|---|---|---|---|
| Neither model has a result on 5 boards here | |||
What each workload costs
Three fixed token mixes at each model's listed price, so per-token rates become a bill.
Chat turn
1K input + 500 output tokens
o3 Mini High costs less
Repository review
50K input + 3K output tokens
o3 Mini High costs less
Agent loop
200K input + 10K output tokens
o3 Mini High costs less
Listed OpenRouter rates, without cache or batch discounts. A workload that does not fit a model's context window would need splitting.
Specification differences
The leading value in a row is marked; a row with a missing value names no leader. Our two rows are marked in red.
| Specification | OpenAI GPT-5.2-Codex | OpenAI o3 Mini High |
|---|---|---|
| Maker | OpenAI | OpenAI |
| Weights | No public weights listed | No public weights listed |
| Released | January 14, 2026 | February 12, 2025 |
| Context window | 400K | 200K |
| Input $/Mtok | $1.75 | $1.10 |
| Output $/Mtok | $14.00 | $4.40 |
| Coding index | 45.4 | Not benchmarked |
| Independent measurements behind it | 3 | 0 |
| Cost per solved task | $0.43 | Not computable |
| Source | OpenRouter listing | OpenRouter listing |
Questions
Is GPT-5.2-Codex better than o3 Mini High for coding?
Only GPT-5.2-Codex has a coding score, 45.4 on the Vibe Coding Index; o3 Mini High has none, so the two cannot be ranked on coding. Pick o3 Mini High for output tokens 3.2x cheaper ($4.40 vs $14.00 per million).
Which is cheaper, GPT-5.2-Codex or o3 Mini High?
GPT-5.2-Codex costs $1.75 per million input tokens and $14.00 per million output tokens; o3 Mini High costs $1.10 and $4.40. Cost per solved task is known for GPT-5.2-Codex only.
Which has the bigger context window, GPT-5.2-Codex or o3 Mini High?
GPT-5.2-Codex, with 400K tokens against 200K.
How many benchmarks is the GPT-5.2-Codex vs o3 Mini High comparison based on?
1 benchmarks have a result for both models as of October 21, 2026. GPT-5.2-Codex's coding index rests on 3 independent benchmarks and o3 Mini High's on 0. Where only one model has a result, the page says so instead of naming a winner.