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GPT-5.4 nanovsStep 3.5 Flash

Step 3.5 Flash leads 1 of 1 shared benchmark. GPT-5.4 nano has the larger context window (400K tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
0 – 1
Step 3.5 Flash leads
Cheaper per token
list price, input + output
Larger context
GPT-5.4 nano
400K tokens
Provider uptime (30d)
94.2446% · —
OpenAI · StepFun
GPT-5.4 nano
OpenAI · released 2026-03-17
textvision
Context
400K
Max out
128K
Input /1M
$0.2
Output /1M
$1.25
Cached /1M
$0.02
Scores
10 · 6 core
Step 3.5 Flash
StepFun · released 2026-02-12
text
Context
256K
Max out
Input /1M
Output /1M
Cached /1M
Scores
18 · 5 core
Quality

Benchmark matrix

BenchmarkGPT-5.4 nanoStep 3.5 FlashΔEdge
Reported by both · 1
Terminal-Bench 2.046.3% 51% -4.7 ptStep 3.5 Flash
Only GPT-5.4 nano reports · 8
GPQA Diamond82.8% not reported
FrontierMath Tier 4 v2 (Epoch AI run)12.2% epochnot reported
FrontierMath Tiers 1-3 v2 (Epoch AI run)44.9% epochnot reported
OSWorld-Verified39% not reported
OTIS Mock AIME 2024-2025 (Epoch AI run)87.8% epochnot reported
SimpleQA Verified11.7% epochnot reported
SWE-Bench Pro52.4% not reported
Toolathlon35.5% not reported
Only Step 3.5 Flash reports · 16
SWE-bench Verifiednot reported74.4%
AIME 2025not reported97.3%
AIME 2026not reported96.7% matharena
LMArena Elonot reported1403.7
BrowseCompnot reported51.6%
BrowseComp (with context manager)not reported69%
BrowseComp-ZHnot reported66.9%
BrowseComp-ZH (with context manager)not reported73.7%
GAIA (no file)not reported84.5%
HMMT 2025 (Feb/Nov average)not reported96.2%
IMOAnswerBenchnot reported85.4%
LiveCodeBench v6not reported86.4%
ResearchRubricsnot reported65.3%
Tau2-Benchnot reported88.2%
xbench-DeepSearch 2025.05not reported83.7%
xbench-DeepSearch 2025.10not reported56.3%
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is GPT-5.4 nano minus Step 3.5 Flash in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecGPT-5.4 nanoStep 3.5 FlashEdge
Context window400K tokens256K tokensGPT-5.4 nano
Max output128K tokens
Input price / 1M$0.2
Output price / 1M$1.25
Cached input / 1M$0.02
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$1.45
Modalitiestext · visiontextGPT-5.4 nano
Released2026-03-172026-02-12
Cited benchmark scores1018
Reliability

Provider status

All providers
More matchups

GPT-5.4 nano vs …

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