LLMBenchmark.ai

Enter opens the highlighted result. Esc closes.

GPT-5.3-Codex vs GPT-5.4

Updated October 21, 2026. 33 benchmarks have a result for both. Coding is ranked on the Vibe Coding Index; every other board is shown as published.

GPT-5.3-CodexOpenAI
Coding
29.5
Overall
32.5
Output $/M
$14.00
8
GPT-5.4OpenAI
Coding
37.7
Overall
39.0
Output $/M
$15.00
25
vs boards won of 33 shared

Decision reading

Pick GPT-5.4 for coding: it scores 37.7 on the Vibe Coding Index against 29.5 for GPT-5.3-Codex.

Pick GPT-5.3-Codex when output tokens cost 1.1x less, or when a solved task costs $0.59 against $1.02.

Shared results
33
GPT-5.3-Codex only
1
GPT-5.4 only
76
Like-for-like categories
6 of 9

Shared results can support a head-to-head reading. Results only one model has describe coverage, not superiority.

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.

At a glance

Coding index
GPT-5.3-Codex 29.5 from 1 benchmark, GPT-5.4 37.7 from 1 benchmark.
Widest category
Web design, 5.0 points apart on average over 8 shared benchmarks.
Widest single gap
LMArena WebDev: React: GPT-5.3-Codex 1395 against GPT-5.4 1454, 9.8 points apart on a 0 to 100 scale.
Output price
GPT-5.3-Codex $14.00 against GPT-5.4 $15.00 per million output tokens, 1.1x apart.
Context window
GPT-5.3-Codex takes 400K tokens, GPT-5.4 1.05M.

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.

Boards won, where both have a result
CategoryGPT-5.3-CodexBarsGPT-5.4Ties
Coding47
Intelligence02
Agentic work26
Reasoning02
Web design08
General20
All shared boards825
CodingLike-for-likeFour of these boards feed the Vibe Coding Index47
Coding benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
LMArena WebDev14071464GPT-5.4
AA Coding IndexNot measured71.1Only GPT-5.4 measured
LiveCodeBench (Vals AI)87.3%84.1%GPT-5.3-Codex
SWE-bench Verified (Vals AI)78.0%78.2%GPT-5.4
Vibe Code Bench (Vals AI)61.8%67.4%GPT-5.4
Code migration (Vals AI)Not measured35.0%Only GPT-5.4 measured
ProgramBench (Vals AI)Not measured0.5%Only GPT-5.4 measured
IOI (Vals AI)53.8%Not measuredOnly GPT-5.3-Codex measured
SkillsBench (Vals AI)Not measured51.7%Only GPT-5.4 measured
Terminal-Bench Hard (Artificial Analysis run)53.0%57.6%GPT-5.4
Terminal-Bench78.4%81.8%GPT-5.4
GSO-BenchNot measured31.4%Only GPT-5.4 measured
WeirdML79.3%77.7%GPT-5.3-Codex
MirrorCodeNot measured15.6%Only GPT-5.4 measured
ALE-Bench1655.21607.0GPT-5.3-Codex
LMArena Text: codingNot measured1496Only GPT-5.4 measured
LMArena Text: software and ITNot measured1491Only GPT-5.4 measured
LMArena WebDev: React13951454GPT-5.4
LMArena WebDev: HTML14221478GPT-5.4
LMArena WebDev: from an image14431436GPT-5.3-Codex
Neither model has a result on the other 18 boards here
IntelligenceLike-for-likePublic boards, shown as published, kept out of the index02
Intelligence benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
AA Intelligence Index32.539.0GPT-5.4
Epoch Capabilities Index157.1157.3GPT-5.4
Agentic workLike-for-likePublic boards, shown as published, kept out of the index26
Agentic work benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
Design Arena: agents building web apps10331059GPT-5.4
Design Arena: agents building full-stack apps9831017GPT-5.4
Design Arena: agents building mobile apps10541087GPT-5.4
Design Arena: agents building Android apps10841037GPT-5.3-Codex
Design Arena: agents building Godot games11241135GPT-5.4
τ²-Bench Telecom86.0%87.1%GPT-5.4
APEX-AgentsNot measured52.4%Only GPT-5.4 measured
METR time horizons74.5%74.3%GPT-5.3-Codex
DeepResearch BenchNot measured35.1%Only GPT-5.4 measured
PostTrainBenchNot measured19.0%Only GPT-5.4 measured
Vending-Bench 2$5,940$6,144GPT-5.4
Neither model has a result on the other 28 boards here
ReasoningLike-for-likePublic boards, shown as published, kept out of the index02
Reasoning benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
GPQA DiamondNot measured91.7%Only GPT-5.4 measured
MMMU Pro (Vals AI)Not measured87.5%Only GPT-5.4 measured
GPQA Diamond (Artificial Analysis run)91.5%92.0%GPT-5.4
Humanity's Last Exam (Artificial Analysis run)42.5%43.7%GPT-5.4
GPQA Diamond (Epoch AI run)Not measured93.3%Only GPT-5.4 measured
ARC-AGINot measured93.7%Only GPT-5.4 measured
ARC-AGI-2Not measured74.0%Only GPT-5.4 measured
Chess puzzlesNot measured48.0%Only GPT-5.4 measured
Mystery game puzzlesNot measured37.0%Only GPT-5.4 measured
EBR-benchNot measured25.4%Only GPT-5.4 measured
LMArena Text: hard promptsNot measured1485Only GPT-5.4 measured
LMArena Text: expertNot measured1507Only GPT-5.4 measured
LMArena Text: hard prompts in EnglishNot measured1479Only GPT-5.4 measured
LMArena Vision: diagramsNot measured1327Only GPT-5.4 measured
LMArena Vision: homeworkNot measured1336Only GPT-5.4 measured
Neither model has a result on the other 6 boards here
MathDirectional onlyPublic boards, shown as published, kept out of the index7 boards, none shared
Math benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
AIMENot measured96.7%Only GPT-5.4 measured
OTIS Mock AIMENot measured97.8%Only GPT-5.4 measured
FrontierMath, tiers 1 to 3Not measured78.6%Only GPT-5.4 measured
FrontierMath, tier 4Not measured49.0%Only GPT-5.4 measured
ProofBenchNot measured56.0%Only GPT-5.4 measured
LMArena Text: mathNot measured1488Only GPT-5.4 measured
LMArena Text: mathematical workNot measured1497Only GPT-5.4 measured
Neither model has a result on the other 6 boards here
KnowledgeDirectional onlyPublic boards, shown as published, kept out of the index13 boards, none shared
Knowledge benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
MMLU ProNot measured87.5%Only GPT-5.4 measured
LegalBench (Vals AI)Not measured86.0%Only GPT-5.4 measured
CaseLaw (Vals AI)Not measured63.8%Only GPT-5.4 measured
CorpFin (Vals AI)Not measured65.3%Only GPT-5.4 measured
TaxEval (Vals AI)Not measured74.0%Only GPT-5.4 measured
MortgageTax (Vals AI)Not measured68.3%Only GPT-5.4 measured
MedQA (Vals AI)Not measured96.1%Only GPT-5.4 measured
MedCode (Vals AI)Not measured41.3%Only GPT-5.4 measured
SimpleQA VerifiedNot measured45.1%Only GPT-5.4 measured
LMArena Text: scienceNot measured1479Only GPT-5.4 measured
LMArena Text: medicine and healthcareNot measured1458Only GPT-5.4 measured
LMArena Text: legal and governmentNot measured1486Only GPT-5.4 measured
LMArena Text: business and financeNot measured1474Only GPT-5.4 measured
Neither model has a result on the other 4 boards here
Web designLike-for-likePublic boards, shown as published, kept out of the index08
Web design benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
Design Arena: websites11631199GPT-5.4
Design Arena: UI components11371215GPT-5.4
Design Arena: game dev11621195GPT-5.4
Design Arena: data viz11641196GPT-5.4
Design Arena: 3D10081065GPT-5.4
Design Arena: all code categories11451180GPT-5.4
Design Arena: SVG11291141GPT-5.4
Design Arena: ASCII art11511188GPT-5.4
Neither model has a result on the other 1 board here
GeneralLike-for-likePublic boards, shown as published, kept out of the index20
General benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
SAGE (Vals AI)Not measured43.3%Only GPT-5.4 measured
MedScribe (Vals AI)Not measured77.5%Only GPT-5.4 measured
IFBench75.4%73.9%GPT-5.3-Codex
Long context reasoning (AA-LCR)83.3%82.0%GPT-5.3-Codex
DTBenchNot measured94.4%Only GPT-5.4 measured
LMCANot measured52.0%Only GPT-5.4 measured
CL-benchNot measured27.9%Only GPT-5.4 measured
Furniture assemblyNot measured37.5%Only GPT-5.4 measured
CL-bench LifeNot measured21.7%Only GPT-5.4 measured
LMArena TextNot measured1469Only GPT-5.4 measured
LMArena Text: instruction followingNot measured1469Only GPT-5.4 measured
LMArena Text: creative writingNot measured1439Only GPT-5.4 measured
LMArena VisionNot measured1303Only GPT-5.4 measured
LMArena Text: EnglishNot measured1467Only GPT-5.4 measured
LMArena Text: non-EnglishNot measured1465Only GPT-5.4 measured
LMArena Text: ChineseNot measured1520Only GPT-5.4 measured
LMArena Text: GermanNot measured1472Only GPT-5.4 measured
LMArena Text: JapaneseNot measured1485Only GPT-5.4 measured
LMArena Text: KoreanNot measured1449Only GPT-5.4 measured
LMArena Text: FrenchNot measured1493Only GPT-5.4 measured
LMArena Text: SpanishNot measured1452Only GPT-5.4 measured
LMArena Text: RussianNot measured1480Only GPT-5.4 measured
LMArena Text: PolishNot measured1472Only GPT-5.4 measured
LMArena Text: multi-turnNot measured1482Only GPT-5.4 measured
LMArena Text: longer queriesNot measured1473Only GPT-5.4 measured
LMArena Text: writing and languageNot measured1458Only GPT-5.4 measured
LMArena Text: entertainment and mediaNot measured1438Only GPT-5.4 measured
LMArena Vision: EnglishNot measured1301Only GPT-5.4 measured
LMArena Vision: ChineseNot measured1354Only GPT-5.4 measured
LMArena Vision: reading textNot measured1312Only GPT-5.4 measured
LMArena Vision: humorNot measured1284Only GPT-5.4 measured
LMArena Vision: recognizing thingsNot measured1251Only GPT-5.4 measured
LMArena Vision: creative writingNot measured1283Only GPT-5.4 measured
LMArena DocumentNot measured1471Only GPT-5.4 measured
Neither model has a result on the other 12 boards here
Image generationNot comparablePublic boards, shown as published, kept out of the index0 boards, none shared
Image generation benchmarks for GPT-5.3-Codex and GPT-5.4
BenchmarkGPT-5.3-CodexGPT-5.4Leader
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

GPT-5.3-Codex$0.0088Fits in one request
GPT-5.4$0.010Fits in one request

GPT-5.3-Codex costs less

Repository review

50K input + 3K output tokens

GPT-5.3-Codex$0.130Fits in one request
GPT-5.4$0.170Fits in one request

GPT-5.3-Codex costs less

Agent loop

200K input + 10K output tokens

GPT-5.3-Codex$0.490Fits in one request
GPT-5.4$0.650Fits in one request

GPT-5.3-Codex 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.

Specifications of GPT-5.3-Codex and GPT-5.4
SpecificationOpenAI GPT-5.3-CodexOpenAI GPT-5.4
MakerOpenAIOpenAI
WeightsNo public weights listedNo public weights listed
ReleasedFebruary 24, 2026March 5, 2026
Context window400K1.05M
Input $/Mtok$1.75$2.50
Output $/Mtok$14.00$15.00
Coding index29.537.7
Independent measurements behind it11
Cost per solved task$0.59$1.02
SourceOpenRouter listingOpenRouter listing

Questions

Is GPT-5.3-Codex better than GPT-5.4 for coding?

Pick GPT-5.4 for coding: it scores 37.7 on the Vibe Coding Index against 29.5 for GPT-5.3-Codex. Pick GPT-5.3-Codex when output tokens cost 1.1x less, or when a solved task costs $0.59 against $1.02.

Which is cheaper, GPT-5.3-Codex or GPT-5.4?

GPT-5.3-Codex costs $1.75 per million input tokens and $14.00 per million output tokens; GPT-5.4 costs $2.50 and $15.00. Per solved SWE-bench Verified task, GPT-5.3-Codex costs $0.59 and GPT-5.4 $1.02.

Which has the bigger context window, GPT-5.3-Codex or GPT-5.4?

GPT-5.4, with 1.05M tokens against 400K.

How many benchmarks is the GPT-5.3-Codex vs GPT-5.4 comparison based on?

33 benchmarks have a result for both models as of October 21, 2026. GPT-5.3-Codex's coding index rests on 1 independent benchmark and GPT-5.4's on 1. Where only one model has a result, the page says so instead of naming a winner.

Compare next