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Model comparison

GPT-5.3 Codex vs GPT-5.4

Data verified

Head-to-head evidence from 19 shared benchmark results across 6 categories. Overall scores shown here use the public BenchAlign v5 ranking lane.

66.69/100
Margin
7.5pts
winning →
OpenAI
74.24/100
1 category wins1 category wins

Public leaderboard positions: GPT-5.3 Codex #26 (Supported); GPT-5.4 #8 (Supported). Intervals and evidence labels describe ranking uncertainty, not a guarantee for a specific workload.

Evidence parity. GPT-5.3 Codex and GPT-5.4 share 19 comparable benchmark results. 2 of 8 categories are comparable. 2 results are unique to GPT-5.3 Codex; 33 to GPT-5.4.

Updated July 20, 2026
Shared results
19
GPT-5.3 Codex only
2
GPT-5.4 only
33
Comparable categories
2 / 8

Pick GPT-5.4 if you want the stronger benchmark profile. GPT-5.3 Codex only becomes the better choice if coding is the priority or you want the cheaper token bill.

Confidence note. This is a partial-evidence comparison with 19 shared benchmark results across 6 evidence categories; 2 of 8 categories currently have scoreable aggregates for both models. Treat the verdict as directional until coverage is more balanced.

Why this result

GPT-5.4 is clearly ahead on the BenchAlign aggregate, 74.24 to 66.69. The gap is large enough that you do not need to squint at the spreadsheet to see the difference.

GPT-5.4's sharpest advantage is in agentic, where it averages 77.2 against 71.4. The single biggest benchmark swing on the page is OSWorld-Verified, 64.7% to 75%. GPT-5.3 Codex does hit back in coding, so the answer changes if that is the part of the workload you care about most.

GPT-5.4 is also the more expensive model on tokens at $2.50 input / $15.00 output per 1M tokens, versus $1.75 input / $14.00 output per 1M tokens for GPT-5.3 Codex. GPT-5.4 gives you the larger context window at 1.05M, compared with 400K for GPT-5.3 Codex.

Category breakdown

Exact category averages are shown below. Not measured means BenchLM does not have enough sourced public coverage for that model and category.

Category scores and score margins for GPT-5.3 Codex and GPT-5.4
CategoryGPT-5.3 CodexΔGPT-5.4
CodingGPT-5.3 Codex67.2Margin 9.5GPT-5.457.7
AgenticGPT-5.3 Codex71.4Margin 5.8GPT-5.477.2
KnowledgeGPT-5.3 CodexNot measuredMarginNo overlapGPT-5.457.6
MathGPT-5.3 CodexNot measuredMarginNo overlapGPT-5.442.5
MultimodalGPT-5.3 CodexNot measuredMarginNo overlapGPT-5.473.2

Decisive benchmark drivers

The largest measured benchmark gaps in this matchup, with exact reported values.

More
A · GPT-5.3 CodexB · GPT-5.4
  1. OSWorld-Verified

    Agentic
    Source ↗
    A 64.7%B 75%
    Winner: GPT-5.4Δ 10.3
    OSWorld-Verified: GPT-5.3 Codex scored 64.7%; GPT-5.4 scored 75%. GPT-5.4 wins this benchmark.
  2. Terminal-Bench 2.0

    Agentic
    Source ↗
    A 77.3%B 75.1%
    Winner: GPT-5.3 CodexΔ 2.2
    Terminal-Bench 2.0: GPT-5.3 Codex scored 77.3%; GPT-5.4 scored 75.1%. GPT-5.3 Codex wins this benchmark.
  3. SWE-bench Pro

    Coding
    Source ↗
    A 56.8%B 57.7%
    Winner: GPT-5.4Δ 0.9
    SWE-bench Pro: GPT-5.3 Codex scored 56.8%; GPT-5.4 scored 57.7%. GPT-5.4 wins this benchmark.

Operational comparison

Runtime and commercial metrics are compared only when both models have a complete sourced value.

MetricGPT-5.3 CodexGPT-5.4Comparison
Input / output priceUSD per 1M tokensGPT-5.3 Codex$1.75 input / $14 outputGPT-5.4$2.5 input / $15 outputGPT-5.3 Codex has the lower combined listed price.
Generation speedtokens per secondGPT-5.3 Codex79 tok/sGPT-5.474 tok/sGPT-5.3 Codex has the higher measured throughput.
First-answer latencyseconds to first tokenGPT-5.3 Codex88.26 sGPT-5.4151.79 sGPT-5.3 Codex reaches the first token sooner.
Context windowmaximum listed tokensGPT-5.3 Codex400KGPT-5.41.05MGPT-5.4 lists the larger context window.

Benchmark Deep Dive

AgenticGPT-5.4 wins
BenchmarkGPT-5.3 CodexGPT-5.4Result
Terminal-Bench 2.0Source 77.3%75.1%GPT-5.3 Codex leads
OSWorld-VerifiedSource 64.7%75%GPT-5.4 leads
τ²-bench resultsSource 86%87.1%GPT-5.4 leads
Gert LabsSource 57.47%64.89%GPT-5.4 leads
JobBenchSource 33.7%38.9%GPT-5.4 leads
CyberGymSource 79.0%Not comparable
BrowseCompSource 82.7%Not comparable
MCP AtlasSource 70.6%Not comparable
ToolathlonSource 54.6%Not comparable
Claw-EvalSource 60.3%Not comparable
DeepSearchQASource 73.6%Not comparable
AA Agentic IndexSource 41.1%Not comparable
APEX-Agents-AASource 33.3%Not comparable
GDPval-AASource 44.7%Not comparable
GDPval-AASource 1395Not comparable
ResearchClawBenchSource 15.3%Not comparable
ExploitGymSource 6.0%Not comparable
CodingGPT-5.3 Codex wins
BenchmarkGPT-5.3 CodexGPT-5.4Result
SWE-bench VerifiedSource 85%Not comparable
SWE-bench ProSource 56.8%57.7%GPT-5.4 leads
SWE-RebenchSource 58.2%Not comparable
Vibe Code BenchSource 61.77%67.42%GPT-5.4 leads
AA-SciCodeSource 53.2%56.6%GPT-5.4 leads
LiveCodeBench ProSource 87.5%Not comparable
React Native EvalsSource 85.3%Not comparable
AA Coding IndexSource 71.0%Not comparable
Reasoning
BenchmarkGPT-5.3 CodexGPT-5.4Result
AA-LCRSource 74.0%74.0%Tie
CritPtSource 16.9%23.4%GPT-5.4 leads
Knowledge
BenchmarkGPT-5.3 CodexGPT-5.4Result
Artificial Analysis Intelligence IndexSource 44.3%51.4%GPT-5.4 leads
AA-GPQA DiamondSource 91.5%92.0%GPT-5.4 leads
AA-HLESource 39.9%41.6%GPT-5.4 leads
AA-Omniscience IndexSource 9.9%5.7%GPT-5.3 Codex leads
AA-Omniscience AccuracySource 51.8%50.0%GPT-5.3 Codex leads
AA-Omniscience Hallucination RateSource 86.9%88.6%GPT-5.3 Codex leads
GPQASource 92.8%Not comparable
HLESource 52.1%Not comparable
HLE w/o toolsSource 39.8%Not comparable
GPQA-DSource 92.8%Not comparable
HealthBench HardSource 40.1%Not comparable
MedXpertQA (Text)Source 59.6%Not comparable
HealthBench ProfessionalSource 48.1%Not comparable
Math
BenchmarkGPT-5.3 CodexGPT-5.4Result
FrontierMath v2 (Tiers 1-3)Source 47.600%Not comparable
FrontierMath v2 (Tier 4)Source 27.100%Not comparable
Multimodal
BenchmarkGPT-5.3 CodexGPT-5.4Result
AA-MMMU-ProSource 78.5%78.4%GPT-5.3 Codex leads
Design Arena WebsiteSource 11951252GPT-5.4 leads
MMMU-ProSource 81.2%Not comparable
OfficeQA ProSource 53.2%Not comparable
MMMU-Pro w/ PythonSource 82.1%Not comparable
CharXivSource 82.8%Not comparable
ERQASource 65.4%Not comparable
SimpleVQASource 61.1%Not comparable
ScreenSpot ProSource 85.4%Not comparable
ZeroBenchSource 41.0%Not comparable
MedXpertQA (MM)Source 77.1%Not comparable
Inst. Following
BenchmarkGPT-5.3 CodexGPT-5.4Result
AA-IFBenchSource 75.4%73.9%GPT-5.3 Codex leads
Frequently Asked Questions (3)

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

GPT-5.4 is ahead on BenchLM's BenchAlign leaderboard, 74.24 to 66.69. The biggest single separator in this matchup is OSWorld-Verified, where the scores are 64.7% and 75%.

Which is better for coding, GPT-5.3 Codex or GPT-5.4?

GPT-5.3 Codex has the edge for coding in this comparison, averaging 67.2 versus 57.7. Inside this category, Vibe Code Bench is the benchmark that creates the most daylight between them.

Which is better for agentic tasks, GPT-5.3 Codex or GPT-5.4?

GPT-5.4 has the edge for agentic tasks in this comparison, averaging 77.2 versus 71.4. Inside this category, OSWorld-Verified is the benchmark that creates the most daylight between them.

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Last updated: July 20, 2026

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